Claude "Unable to Authenticate": How to Fix Login Errors on Claude.ai, Desktop and Claude Code

Seeing "unable to authenticate" or a similar login error in Claude is frustrating, because the message rarely says what went wrong. The cause depends on where you are signing in: the Claude website, the desktop app, or Claude Code in a terminal.

This guide follows Anthropic's own support pages and Claude Code documentation. Find your error in the table first, then jump to the fix.

Find Your Error

Quick Checks Before You Start

These take a minute and solve many cases:

• Open status.claude.com and check for an active incident.
• Make sure your device clock is accurate. Claude Code's token validation depends on correct timestamps.
• Try the same account on another device or in a private browser window.

If the status page shows an outage, wait for it to clear before you change anything.

Fix 1: Generic Login Error on Claude.ai

If you see a general error such as "There was an error logging you in," Anthropic recommends these steps:

1. Turn off your VPN. Anthropic says to make sure you are not using a VPN when you access Claude.
2. Disable browser extensions. Switch off active extensions, then try again.
3. Clear your browser's cache and cookies.
4. Check status.claude.com if the problem continues.

Fix 2: The Login Email Does Not Arrive

Claude does not use passwords. You sign in with Google or with an email link, so a missing email blocks you completely.

• The email subject is "Secure link to log in to Claude.ai."
• Check spam or junk folders for messages from @mail.anthropic.com, and add that sender to your safe list.
• Wait a few minutes and request the link again.
• If you use a work email, your IT team may need to allow the message through its security filter.

If you open the link on a different device than the one you started on, you get a verification code to type into the original device. Use the same device when you can, because the link then logs you in automatically.

Fix 3: "Unable to Verify You With This Link" (Desktop App)

Some users report this message in the Claude desktop app while signing in works in a browser. One public GitHub report describes it on Windows 10 with both Google sign-in and email codes, and the issue was later closed as fixed. Anthropic has not published an official troubleshooting page for this exact message, so try these steps in order:

1. Update the desktop app to the latest version.
2. Sign in on claude.ai in your browser to confirm your account works.
3. Sign out of the desktop app completely, restart it, and try again.
4. Use the email code option instead of the link if the app offers it.

Fix 4: "Not Logged In" or Token Expired (Claude Code)

Messages such as "Not logged in · Please run /login," "Login expired" or "OAuth token has expired" mean your session ended. According to Anthropic's docs:

1. Run /login inside Claude Code and sign in again.
2. If it keeps happening, check that your system clock is correct.

If login still fails and the cause is unclear, do a clean re-authentication:

1. Run /logout.
2. Close Claude Code.
3. Start it again with claude and complete the sign-in.

If the browser does not open on its own, press c to copy the sign-in URL and paste it into a browser yourself.

macOS users: Claude Code stores credentials in the login Keychain. If the Keychain is locked or out of sync, it may save your login to a plain file instead, and some logins can fail. Run claude doctor to check, and look for a warning that starts with "macOS Keychain is not writable." To unlock it:

security unlock-keychain ~/Library/Keychains/login.keychain-db

Then run claude doctor again. If the warning remains, open Keychain Access, select the login keychain, and use Edit > Change Password for Keychain "login" to match your account password. Finish with /logout and /login. Note that logging out removes saved MCP server logins and plugin secrets, so you will need to enter them again.

Fix 5: "OAuth Error: Invalid Code" (Claude Code)

This means the login code expired or was cut off when you pasted it. Anthropic suggests:

• Press Enter to retry and finish the login quickly after the browser opens.
• Type c to copy the whole URL if the browser does not open automatically.
• On a remote or SSH session, copy the URL from the terminal and open it in the browser on your own computer.

Fix 6: 403 Forbidden After Login (Claude Code)

If you see "API Error: 403 Request not allowed," check these:

• Claude Pro or Max users: Confirm your subscription is active in your claude.ai settings.
• Anthropic Console users: Confirm your account has the "Claude Code" or "Developer" role. An admin assigns this in the Console under Settings, then Members.
• Behind a proxy: A corporate proxy can block API requests, so ask your IT team about the proxy settings.

If you see "Claude Code access has not been granted for this account," your Claude Enterprise organization likely gave you a Custom role without Claude Code access. Only an Owner of your organization can fix it, by assigning a role that includes Claude Code.

Fix 7: "Organization Has Been Disabled" With an Active Subscription

If you pay for Claude but see "This organization has been disabled," an old ANTHROPIC_API_KEY is probably overriding your subscription. This often happens when a key from a previous job or project is still set in your shell profile.

On macOS or Linux:

unset ANTHROPIC_API_KEY
claude

On Windows PowerShell:

Remove-Item Env:ANTHROPIC_API_KEY
claude

To make it permanent, remove any export ANTHROPIC_API_KEY=... line from ~/.zshrc, ~/.bashrc or ~/.profile. On Windows, also check your PowerShell profile and your User environment variables. Run /status inside Claude Code to confirm which sign-in method is active.

Fix 8: Login Fails in WSL2, SSH or Containers

In these setups the browser usually opens on a different machine, so it cannot send the login result back to Claude Code. After you sign in, the browser shows a code. Paste that code into the terminal at the "Paste code here if prompted" prompt.

If the browser does not open from WSL2, set the BROWSER variable to your Windows browser:

export BROWSER="/mnt/c/Program Files/Google/Chrome/Application/chrome.exe"
claude

If pasting does nothing in the interactive prompt, use this command, which reads the pasted code from standard input:

claude auth login

Other Errors You May See

Still Stuck?

Run claude doctor in your terminal for an automated diagnostic report. Inside a session, /doctor gives a setup checkup, and /feedback reports the problem to Anthropic. For account or billing problems, sign in at claude.ai, click your initials in the lower left, and choose Get help.

If your plan is the issue, see our guides on Claude Pro pricing in India and what Claude Sonnet 5 offers before you decide on a subscription.

Frequently Asked Questions