Find your error
Match the error message or symptom you’re seeing to a fix:
If your issue isn’t listed, work through the diagnostic checks below to narrow down the cause.
Run diagnostic checks
Check network connectivity
The installer downloads fromdownloads.claude.ai. Verify you can reach it:
curl.exe -sI instead. PowerShell aliases curl to Invoke-WebRequest, which rejects the -sI flags.
An HTTP/2 200 line means you reached the server. Other results point to the cause:
403: usually a proxy or network filter blocking the host, or Claude Code is not available in your region5xx: usually a temporary service issue; wait a few minutes and retry
Could not resolve host, or a connection timeout, your network is blocking the connection. Common causes:
- Corporate firewalls or proxies blocking
downloads.claude.ai - Regional network restrictions: try a VPN or alternative network
- TLS/SSL issues: update your system’s CA certificates, or check if
HTTPS_PROXYis configured
HTTPS_PROXY and HTTP_PROXY to your proxy’s address before installing. Ask your IT team for the proxy URL if you don’t know it, or check your browser’s proxy settings.
This example sets both proxy variables, then runs the installer through your proxy:
- macOS/Linux
- Windows PowerShell
Verify your PATH
If installation succeeded but you get acommand not found or not recognized error when running claude, the install directory isn’t in your PATH. Your shell searches for programs in directories listed in PATH, and the installer places claude at ~/.local/bin/claude on macOS/Linux or %USERPROFILE%\.local\bin\claude.exe on Windows.
The VS Code extension does not place
claude at this location. It bundles a private copy of the CLI inside the extension directory for its own chat panel and does not add it to PATH. If you have only installed the extension, ~/.local/bin/claude will not exist. Run the standalone install to use claude from a terminal, then continue below.local/bin:
- macOS/Linux
- Windows PowerShell
- Windows CMD
/Users/you/.local/bin or /home/you/.local/bin, the directory is in your PATH and you can skip to Check for conflicting installations. If there’s no output, add it to your shell configuration.For Zsh, the default on macOS:~/.local/bin to your PATH using your shell’s own configuration syntax, then restart your terminal.Verify the fix worked:Check for conflicting installations
Multiple Claude Code installations can cause version mismatches or unexpected behavior. Check what’s installed:- macOS/Linux
- Windows PowerShell
List all If this prints nothing, no A native install shows a symlink into
claude binaries found in your PATH:claude is on your PATH yet. Go back to Verify your PATH.Check the three locations a claude binary can come from. ~/.local/bin/claude is the native installer, ~/.claude/local/ is a legacy local npm install created by older versions of Claude Code, and the npm global list shows a -g install:~/.local/share/claude/versions/. A script or a symlink you created yourself at this path is a custom launcher, which auto-update leaves in place.If either ls command prints No such file or directory, that’s not an error. It means nothing is installed at that location, so move on to the next check.~/.local/bin/claude on macOS/Linux or %USERPROFILE%\.local\bin\claude.exe on Windows is recommended. Remove the extras:
Uninstall an npm global install:
claude-code@latest cask, substitute that name:
Check directory permissions
The installer needs write access to~/.local/bin/ and ~/.claude/ on macOS and Linux. On Windows the install location is under %USERPROFILE%, which is writable by your user by default, so this section rarely applies there.
Check whether the directories are writable:
Verify the binary works
Ifclaude --version prints a version but claude crashes or hangs on startup, run these checks to narrow down the cause. If claude --version says command not found, go to Verify your PATH first; the commands below assume claude is on your PATH.
Confirm the binary exists and is executable:
ldd shows missing libraries, you may need to install system packages. On Alpine Linux and other musl-based distributions, see Alpine Linux setup.
Common installation issues
These are the most frequently encountered installation problems and their solutions.Install script returns HTML instead of a shell script
When running the install command, you may see one of these errors:iex trying to run HTML and CSS as PowerShell:
Missing expression after unary operator '--' or a ParserError with ParseException instead. HTML tags or CSS in the quoted text identify this failure. If you download with -OutFile install.ps1 instead, the saved file is the same web page, so that doesn’t help either.
Depending on how the request was routed, you may instead see a 403 with no HTML body:
-
Use an alternative install method:
On macOS, install via Homebrew:
On Windows, install via WinGet:
- Retry after a few minutes: the issue is often temporary. Wait and try the original command again.
command not found: claude after installation
The install finished but claude doesn’t work. The exact error varies by platform:
This means the install directory isn’t in your shell’s search path. See Verify your PATH for the fix on each platform.
curl: (56) Failure writing output to destination
The curl ... | bash command downloads the script and pipes it to Bash for execution. This error, and the related curl: (23) Failure writing output to destination, means Bash did not receive the complete script. Exit code 56 indicates the download itself was interrupted, and exit code 23 indicates curl could not write what it received to the pipe, usually because Bash exited early.
Solutions:
-
Check network stability: Claude Code binaries are hosted at
downloads.claude.ai. Test that you can reach it:AnHTTP/2 200line means you reached the server and the original failure was likely intermittent; retry the install command. Other results point to the cause:403: usually a proxy or network filter blocking the host, or Claude Code is not available in your region5xx: usually a temporary service issue; wait a few minutes and retryCould not resolve hostor a connection timeout: your network is blocking the download
-
Try an alternative install method:
On macOS:
On Windows:
Homebrew cask unavailable or outdated
Homebrew reportsError: Cask 'claude-code' is unavailable: No Cask with this name exists when your local copy of the Homebrew cask index predates the cask’s publication. Refresh the index and retry:
claude-code cask tracks the stable channel and is typically about one week behind the latest release; for the newest version run brew install --cask claude-code@latest instead. See Configure release channel for the difference between the two casks.
TLS or SSL connection errors
Errors likecurl: (35) TLS connect error, schannel: next InitializeSecurityContext failed, or PowerShell’s Could not establish trust relationship for the SSL/TLS secure channel indicate TLS handshake failures.
Solutions:
-
Update your system CA certificates:
On Ubuntu/Debian:
On macOS, the system curl uses the Keychain trust store; updating macOS itself updates the root certificates.
-
On Windows, enable TLS 1.2 in PowerShell before running the installer:
-
Check for proxy or firewall interference: corporate proxies that perform TLS inspection can cause these errors, including
unable to get local issuer certificateandSELF_SIGNED_CERT_IN_CHAIN. For the install step, point curl at your corporate CA bundle with--cacert:For Claude Code itself once installed, setNODE_EXTRA_CA_CERTSso API requests trust the same bundle:Ask your IT team for the certificate file if you don’t have it. You can also try on a direct connection to confirm the proxy is the cause. -
On Windows, switch installers if your network blocks revocation checks. The errors
CRYPT_E_NO_REVOCATION_CHECK (0x80092012)andCRYPT_E_REVOCATION_OFFLINE (0x80092013)mean curl reached the server but your network blocks the certificate revocation lookup, which is common behind corporate firewalls. Adding curl’s--ssl-revoke-best-effortflag doesn’t fix this: the flag only applies to downloadinginstall.cmditself, and the script’s own downloads run without it, so the install fails with the same error. Use an install method that tolerates the blocked lookup instead. Open PowerShell and run the PowerShell installer, which downloads through .NET and doesn’t fail when the revocation server is unreachable:You can also install withwinget install Anthropic.ClaudeCode, which avoids curl entirely.
Failed to fetch version from downloads.claude.ai
The installer couldn’t reach the download server. This typically means downloads.claude.ai is blocked on your network.
Solutions:
-
Test connectivity directly:
An
HTTP/2 200line means the server is reachable. Other results point to the cause:403: usually a proxy or network filter blocking the host, or Claude Code is not available in your region5xx: usually a temporary service issue; wait a few minutes and retry
-
If behind a proxy, set
HTTPS_PROXYso the installer can route through it. See proxy configuration for details. -
If on a restricted network, try a different network or VPN, or use an alternative install method:
On macOS:
On Windows:
Wrong install command on Windows
If you see'irm' is not recognized, The token '&&' is not valid, A parameter cannot be found that matches parameter name 'fsSL', or 'bash' is not recognized as the name of a cmdlet, you copied the install command for a different shell or operating system.
-
irmnot recognized: you’re in CMD, not PowerShell. You have two options: Open PowerShell by searching for “PowerShell” in the Start menu, then run the original install command:Or stay in CMD and use the CMD installer instead: -
&¬ valid: you’re in PowerShell but ran the CMD installer command. Use the PowerShell installer: -
A parameter cannot be found that matches parameter name 'fsSL': you ran the macOS/Linuxcurl -fsSL ... | bashinstaller in Windows PowerShell, wherecurlis an alias forInvoke-WebRequestand rejects the-fsSLflags. Use the PowerShell installer instead: -
bashnot recognized: you ran the macOS/Linux installer on Windows. Use the PowerShell installer instead:
running scripts is disabled on this system
Installing or running Claude Code through npm on Windows can fail with a SecurityError:
claude.ps1 when you run claude after an npm install. PowerShell’s execution policy is blocking the .ps1 launcher scripts that npm creates for its commands. The policy applies to script files, so it doesn’t affect the PowerShell installer irm https://claude.ai/install.ps1 | iex, which runs the downloaded text directly.
Solutions:
- Allow locally created scripts for your user, then retry:
- Call the
.cmdlauncher instead:npm.cmdandclaude.cmddo the same job, and the policy doesn’t cover them. - Use the PowerShell installer instead of npm. It installs a binary rather than a
.ps1script.
The process cannot access the file during Windows install
If the PowerShell installer fails with Failed to download binary: The process cannot access the file ... because it is being used by another process, the installer couldn’t write to %USERPROFILE%\.claude\downloads. This usually means a previous install attempt is still running, or antivirus software is scanning a partially downloaded binary in that folder.
Close any other PowerShell windows running the installer and wait for antivirus scans to release the file. Then delete the downloads folder and run the installer again:
Install killed on low-memory Linux servers
AKilled message during install usually means the Linux out-of-memory (OOM) killer terminated the claude install step because the system ran out of free memory. This is common on small VPS and cloud instances. The install script reports the cause and exits with code 137:
Killed line and no explanation.
Installing needs roughly 512 MB of free memory, and running Claude Code needs more. See the system requirements.
Solutions:
-
Add swap space if your server has limited RAM. Swap uses disk space as overflow memory, letting the install complete even with low physical RAM.
Create a 2 GB swap file and enable it:
Then retry the installation:
- Close other processes to free memory before installing.
- Use a larger instance if possible. Claude Code requires at least 4 GB of RAM.
Install hangs in Docker
When installing Claude Code in a Docker container, installing as root into/ can cause hangs.
Solutions:
-
Set a working directory before running the installer. When run from
/, the installer scans the entire filesystem, which causes excessive memory usage. SettingWORKDIRlimits the scan to a small directory: -
Increase Docker memory limits if using Docker Desktop:
claude update or claude doctor hangs
claude update and claude doctor scan your shell configuration files for an outdated claude alias: ~/.zshrc, ~/.bashrc, and ~/.config/fish/config.fish, plus on macOS the first of ~/.bash_profile, ~/.bash_login, or ~/.profile that exists. If you set ZDOTDIR, the Zsh file is $ZDOTDIR/.zshrc instead. When one of those paths is a directory, Claude Code skips it and both commands complete normally. Before v2.1.214, a directory at one of those paths made both commands hang and left the System diagnostics section of /status blank. claude doctor hung with no output; claude update hung right after printing Checking for updates.
If you hit the hang on an earlier version, find the directory. In this command’s output, a line starting with d marks that path as a directory. A No such file or directory line means nothing exists at that path and isn’t the cause:
claude update hangs on the affected versions, update by rerunning the install script instead.
Claude Desktop overrides the claude command on Windows
If you installed an older version of Claude Desktop, it may register a Claude.exe in the WindowsApps directory that takes PATH priority over Claude Code CLI. Running claude opens the Desktop app instead of the CLI.
Update Claude Desktop to the latest version to fix this issue.
Claude Code on Windows requires either Git for Windows (for bash) or PowerShell
Git for Windows is optional. Claude Code uses the PowerShell tool when Git Bash is absent, so this error means neither shell was found. If PowerShell is missing from your PATH, its default location isC:\Windows\System32\WindowsPowerShell\v1.0\. Add that directory to your PATH, or install PowerShell 7, which provides pwsh.
To install Git for Windows instead, download it from git-scm.com/downloads/win. During setup, select “Add to PATH.” Restart your terminal after installing. Installing it enables the Bash tool, useful when working with Bash-based scripts and tooling.
If Git is already installed but Claude Code can’t find it, set the path in your settings.json file:
where.exe git in PowerShell and use the bin\bash.exe path from that directory.
If the path is correct and the file exists but Claude Code still doesn’t use it, check the file’s name first. Claude Code accepts only a file named bash.exe, sh.exe, bash, or sh; with any other name, such as Git for Windows’ git-bash.exe launcher, it ignores the variable and auto-detects Git Bash as if it were unset, logging a warning visible with --debug. A path that doesn’t exist gets the same fallback and warning. Before v2.1.219, Claude Code used any existing file as the shell without checking its name, and exited at startup with Claude Code was unable to find CLAUDE_CODE_GIT_BASH_PATH path when the path didn’t exist.
If the file’s name is right, endpoint security software such as AppLocker, Group Policy software restriction policies, or EDR agents may be interfering. On versions before v2.1.116, Claude Code spawned a cmd.exe child process to verify the path, which these policies can block. A common signal is that cmd.exe /c dir "C:\Program Files\Git\bin\bash.exe" works when you run it directly in PowerShell but fails silently when launched by claude.exe.
Claude Code v2.1.116 and later check the filesystem directly, so update first. If the error persists on a current version, ask your IT team to allowlist claude.exe and the processes it spawns, including cmd.exe and bash.exe, in your endpoint protection policy.
Claude Code does not support 32-bit Windows
Windows includes two PowerShell entries in the Start menu:Windows PowerShell and Windows PowerShell (x86). The x86 entry runs as a 32-bit process and triggers this error even on a 64-bit machine. To check which case you’re in, run this in the same window that produced the error:
True, your operating system is fine. Close the window, open Windows PowerShell without the x86 suffix, and run the install command again.
If this prints False, you are on a 32-bit edition of Windows. Claude Code requires a 64-bit operating system. See the system requirements.
Linux musl or glibc binary mismatch
If you see errors about missing shared libraries likelibstdc++.so.6 or libgcc_s.so.1 after installation, the installer may have downloaded the wrong binary variant for your system.
-
Check which libc your system uses:
Output mentioning
GNU libcorGLIBCmeans glibc. Output mentioningmuslmeans musl. -
If you’re on glibc but got the musl binary, remove the installation and reinstall. You can also manually download the correct binary using the manifest at
https://downloads.claude.ai/claude-code-releases/{VERSION}/manifest.json. File a GitHub issue with the output ofldd --versionandls /lib/libc.musl*. -
If you’re actually on musl, such as Alpine Linux, install the required packages:
On Alpine,
ripgrepis in the community repository. Ifapkreports that the package is missing, see Alpine Linux setup.
Illegal instruction
If running claude or the installer prints Illegal instruction, the native binary uses CPU instructions your processor doesn’t support. There are two distinct causes.
Architecture mismatch. The installer downloaded the wrong binary, for example x86 on an ARM server. Check with uname -m on macOS or Linux, or $env:PROCESSOR_ARCHITECTURE in PowerShell. If the result doesn’t match the binary you received, file a GitHub issue with the output.
Missing AVX instruction set. If your architecture is correct but you still see Illegal instruction, your CPU likely lacks AVX or another instruction the binary requires. This affects roughly pre-2013 Intel and AMD processors, and virtual machines where the hypervisor does not pass AVX through to the guest.
On a VPS or VM, run grep -m1 -ow avx /proc/cpuinfo; an empty result means AVX is not available to the guest.
There is no native-binary workaround; track issue #50384 for status, and include your CPU model from grep -m1 "model name" /proc/cpuinfo on Linux or sysctl -n machdep.cpu.brand_string on macOS when reporting.
Alternative install methods download the same native binary and won’t resolve either cause.
dyld: cannot load on macOS
If you see dyld: cannot load, dyld: Symbol not found, or Abort trap: 6 during installation, the binary is incompatible with your macOS version or hardware.
Symbol not found error that references libicucore also indicates your macOS version is older than the binary supports:
- Check your macOS version: Claude Code requires macOS 13.0 or later. Open the Apple menu and select About This Mac to check your version.
- Update macOS if you’re on an older version. The binary uses load commands and system libraries that older macOS versions don’t support. Alternative install methods like Homebrew download the same binary and won’t resolve this error.
Exec format error on WSL1
If running claude in WSL prints cannot execute binary file: Exec format error, you’re on WSL1 and hitting a known native-binary regression tracked in issue #38788. The binary’s program headers changed in a way WSL1’s loader can’t handle.
The cleanest fix is to convert your distribution to WSL2 from PowerShell:
~/.bashrc inside WSL, replacing the path if your home directory differs:
source ~/.bashrc and retry claude.
npm install errors in WSL
These issues apply if you installed Claude Code withnpm install -g inside WSL. If you used the native installer, skip this section.
OS or platform detection issues. If npm reports a platform mismatch during install, WSL is likely picking up the Windows npm. Run npm config set os linux first, then install with npm install -g @anthropic-ai/claude-code --force. Do not use sudo.
exec: node: not found when running claude. Your WSL environment is likely using the Windows installation of Node.js. Confirm with which npm and which node: paths starting with /mnt/c/ are Windows binaries, while Linux paths start with /usr/. To fix this, install Node via your Linux distribution’s package manager or via nvm.
nvm version conflicts. If you have nvm installed in both WSL and Windows, switching Node versions in WSL may break because WSL imports the Windows PATH by default and the Windows nvm takes priority. The most common cause is that nvm isn’t loaded in your shell. Add the nvm loader to ~/.bashrc or ~/.zshrc:
Permission errors during installation
If the native installer fails with permission errors, the target directory may not be writable. See Check directory permissions. If you previously installed with npm and are hitting npm-specific permission errors, switch to the native installer:Native binary not found after npm install
The@anthropic-ai/claude-code npm package downloads the native binary as a per-platform optional dependency, such as @anthropic-ai/claude-code-darwin-arm64. npm then runs the package’s postinstall script, which copies that binary into place as the claude command; until it runs, claude is a placeholder script. If either the download or the postinstall step is skipped, the placeholder stays in place, and running claude on macOS and Linux prints:
bin/claude.exe is that same shell-script placeholder rather than a real executable, so PowerShell and CMD report that they can’t run the file instead of printing this message.
Check the following causes:
- Optional dependencies are disabled. Remove
--omit=optionalfrom your npm install command,--no-optionalfrom pnpm, or--ignore-optionalfrom yarn, and check that.npmrcdoes not setoptional=false. Then reinstall. The native binary is delivered only as an optional dependency, so there is no JavaScript fallback if it is skipped, and runninginstall.cjsagain can’t place a binary that was never downloaded. - Install scripts are disabled.
--ignore-scriptsand some pnpm configurations skip the postinstall step but still download the platform package. Runnode node_modules/@anthropic-ai/claude-code/install.cjsas the message suggests, or reinstall without the flag. If postinstall can’t run in your environment at all,node node_modules/@anthropic-ai/claude-code/cli-wrapper.cjsfinds the downloaded package and launches it, at the cost of an extra Node process on each start. If the wrapper printsCould not find native binary packageinstead, the platform package was never downloaded, so fix the optional-dependencies cause above first. - Unsupported platform. Prebuilt binaries are published for
darwin-arm64,darwin-x64,linux-x64,linux-arm64,linux-x64-musl,linux-arm64-musl,win32-x64, andwin32-arm64. Claude Code does not ship a binary for other platforms; see the system requirements. On FreeBSD, the installer reports the platform as unsupported. Before v2.1.205, it treated FreeBSD as Linux and downloaded a binary that couldn’t run. - Corporate npm mirror is missing the platform packages. Ensure your registry mirrors all eight
@anthropic-ai/claude-code-*platform packages in addition to the meta package.
Login and authentication
These sections address login failures, OAuth errors, and token issues.Reset your login
When login fails and the cause isn’t obvious, a clean re-authentication resolves most cases:- Run
/logoutto sign out completely - Close Claude Code
- Restart with
claudeand complete the authentication process again
c to copy the OAuth URL to your clipboard, then paste it into a browser manually. This also works when the URL wraps across lines in a narrow or SSH terminal and can’t be clicked directly.
OAuth error: Invalid code
If you seeOAuth error: Invalid code. Please make sure the full code was copied, the login code expired or was truncated during copy-paste.
Solutions:
- Press Enter to retry and complete the login quickly after the browser opens
- Type
cto copy the full URL if the browser doesn’t open automatically - If using a remote/SSH session, the browser may open on the wrong machine. Copy the URL displayed in the terminal and open it in your local browser instead.
403 Forbidden after login
If you seeAPI Error: 403 {"error":{"type":"forbidden","message":"Request not allowed"}} after logging in:
- Claude Pro/Max users: verify your subscription is active at claude.ai/settings
- Anthropic Console users: confirm your account has the “Claude Code” or “Developer” role. Admins assign this in the Anthropic Console under Settings → Members.
- Behind a proxy: corporate proxies can interfere with API requests. See network configuration for proxy setup.
This organization has been disabled with an active subscription
If you seeAPI Error: 400 ... "This organization has been disabled" despite having an active Claude subscription, an ANTHROPIC_API_KEY environment variable is overriding your subscription. This commonly happens when an old API key from a previous employer or project is still set in your shell profile.
When ANTHROPIC_API_KEY is present and you have approved it, Claude Code uses that key instead of your subscription’s OAuth credentials. In non-interactive mode with the -p flag, the key is always used when present. See authentication precedence for the full resolution order.
To use your subscription instead, unset the environment variable and remove it from your shell profile:
~/.zshrc, ~/.bashrc, or ~/.profile for export ANTHROPIC_API_KEY=... lines and remove them to make the change permanent. On Windows, check your PowerShell profile at $PROFILE and your User environment variables for ANTHROPIC_API_KEY. Run /status inside Claude Code to confirm which authentication method is active.
OAuth login fails in WSL2, SSH, or containers
When Claude Code runs in WSL2, on a remote machine over SSH, or inside a container, the browser usually opens on a different host and its redirect can’t reach Claude Code’s local callback server. After you sign in, the browser shows a login code instead of redirecting back automatically. Paste that code into the terminal at thePaste code here if prompted prompt to complete login.
If the browser doesn’t open at all from WSL2, set the BROWSER environment variable to your Windows browser path:
c at the interactive login prompt to copy the OAuth URL, or copy the URL that claude auth login prints, and open it in a browser on your local machine.
If pasting the code into the interactive prompt does nothing, your terminal’s paste binding likely isn’t reaching the input field. Try your terminal’s alternate paste shortcut, often right-click or Shift+Insert in Windows Terminal, or use claude auth login instead, which reads the pasted code from standard input:
Not logged in or token expired
If Claude Code prompts you to log in again after a session, your OAuth token may have expired. Run/login to re-authenticate. If this happens frequently, check that your system clock is accurate, as token validation depends on correct timestamps.
Parallel sessions on one machine share a saved login and coordinate its renewal so that only one process refreshes the token at a time. Before v2.1.211, waking the machine from sleep could cause two sessions to renew with the same token, which revoked the saved login and prompted every open session to log in again at once.
On macOS, login can also fail when the Keychain is locked or its password is out of sync with your account password, which prevents Claude Code from saving credentials. Run claude doctor to check Keychain access. To unlock the Keychain manually, run security unlock-keychain ~/Library/Keychains/login.keychain-db. If unlocking doesn’t help, open Keychain Access, select the login keychain, and choose Edit > Change Password for Keychain “login” to resync it with your account password.
Bedrock, Agent Platform, or Foundry credentials not loading
If you configured Claude Code to use a cloud provider and seeCould not load credentials from any providers on Amazon Bedrock, Could not load the default credentials on Google Cloud’s Agent Platform, or ChainedTokenCredential authentication failed on Microsoft Foundry, your cloud provider CLI is likely not authenticated in the current shell.
For Amazon Bedrock, confirm your AWS credentials are valid:
ANTHROPIC_VERTEX_PROJECT_ID and CLOUD_ML_REGION are set in your shell, then set application default credentials:
ANTHROPIC_FOUNDRY_API_KEY is set, or sign in with the Azure CLI so the default credential chain can find your account:
Still stuck
If none of the above resolves your issue:- Check the GitHub repository for known issues, or open a new one with your operating system, the install command you ran, and the full error output
- If
claude --versionworks but something else is wrong, runclaude doctorfor an automated diagnostic report - If you can start a session, use
/feedbackinside Claude Code to report the problem - If the problem is with your account rather than the install, such as a login loop, a subscription that isn’t recognized, or a disabled organization, contact Anthropic support: sign in at claude.ai (Console users: platform.claude.com), click your initials in the lower left, and select Get help. See How to get support for the full flow.