Identify whether the loop is in verification, redirect, or sign-in

First checks for Claude verification and sign-in loops
SymptomCheck firstKeep a record of
Verification returns to the same pageCookies, site data, redirects, or extension blockingURLs before and after the redirect and full message
Sign-in immediately returns to signed outSign-in method, session, device time, and site dataMethod used and failed step
Only one browser loopsExtensions, privacy settings, and content blocking in that browserPrivate-window or clean-profile comparison
Only one network loopsDNS, exit, proxy rules, and address familyIPv4, IPv6, ASN, and check time
The same account message appears across networksPage guidance, service status, and official supportExact text and reproduction scope

Use a clean session to isolate cookies and blocking

  1. Confirm the sign-in method

    Use the same method originally used to register or link the account. Switching identity providers repeatedly inside a loop creates a poor comparison.

  2. Test a private window or clean profile

    Do not clear every browser setting at once. First reproduce in a private window or new profile to see whether stored site data or extensions are involved.

  3. Review required cookies and redirects

    Temporarily disable an extension that blocks Claude-related scripts, cookies, or redirects, then retest one setting at a time and restore needed protections after diagnosis.

  4. Check device time and browser version

    Incorrect system time and outdated browsers can affect secure sessions and redirects. Update, then repeat the same flow once.

  5. Keep the exact message that remains

    If a clean browser also reproduces the issue, save the exact text, time, and triggering action before comparing a network or contacting support.

Inspect the network only when it changes the result

Only after the issue remains in a clean session and the same browser and sign-in method recover on another known-stable network should you inspect the original DNS, proxy path, Claude routing exit, and IPv4/IPv6 consistency. TLS inspection and content filtering on managed networks can also affect challenge or redirect resources.

The Claude and routing-exit checks record the current network path; they cannot complete verification by changing an IP. Do not treat a check result as a verification pass rate or account score, and do not try to bypass the page's verification controls.

Compare with the fewest variables

  • Browser A: the original setup; browser B: a private window or clean profile
  • Network A: the current network; network B: one known-stable network
  • Use the same sign-in method and record whether the failure occurs at verification, redirect, or after sign-in
  • Record IPv4, IPv6, region, ASN, and the Claude routing exit separately
  • Change either the browser or network per test, not several nodes at once

When to stop local troubleshooting

When the same account or page message repeats in a clean browser, another device, and another stable network, local exit comparison has limited value. Review Claude Status, then use Anthropic support with the full message, time, sign-in method, and controlled tests already completed.

Sources and evidence limits

Sources below support the stated technical or policy boundary. Diagnostic comparisons in this guide remain observations, not account verdicts.