Copilot sign in not working, account not recognized

The behavior matches an account/identity conflict rather than a browser issue. Use these steps to break the loop and re-establish the account cleanly:

1. Confirm the Microsoft account is active and recognized
   • Go to the Microsoft account sign-in page and sign in with the email and password that work for Microsoft/Xbox.
   • If any sign-in problems appear (password not working, username not recognized, verification issues), resolve them first using the account recovery tools:
     • Reset password if needed.
     • Use the Sign-in Helper if the username or account is reported as not existing.
   • Follow the guidance in “I can't sign in to my Microsoft account” to make sure the account itself is healthy and recognized across Microsoft services.
2. Check for “account doesn’t exist” vs. “already exists” conditions
   • If Copilot says “account doesn’t exist” when signing in, but “account already exists” when trying to create one, it indicates stale identity data or conflicting records for that email.
   • Because the old account was deleted and a new one created with the same email, some services (like Copilot) may still reference the old, deleted identity while others see the new one.
3. Clear cached sign-in state in the browser
   • In Edge and Brave, sign out of all Microsoft accounts.
   • Clear cookies and site data specifically for Microsoft-related domains (for example, sign-in and account pages) so the browser stops reusing old tokens.
   • Close all browser windows, reopen, and then sign in again with the current Microsoft account.
4. Verify sign-in health for the Microsoft account
   • If the account is still sometimes reported as not existing, or loops on sign-in, follow the “Steps to recover your Microsoft account” flow:
     • If you see “We couldn't find an account with that username” or “account doesn't exist,” use the Sign-in Helper tool.
     • If the username has “stopped working,” follow the “My username has stopped working” guidance.
5. If the loop persists only for Copilot
   • After confirming the Microsoft account is fully working on other Microsoft services (Outlook.com, Microsoft account portal, Xbox, etc.), and browser cache has been cleared, the remaining issue is likely service-side identity data for Copilot.
   • At that point, contact Microsoft Support and provide:
     • The exact email address (masked if sharing publicly).
     • Screenshots or text of both messages: “account doesn’t exist” and “account already exists.”
     • Confirmation that the old account was deleted and a new one created with the same email.
   • Support can check and correct the backend identity mapping for Copilot.

These steps ensure the Microsoft account itself is valid and recognized, remove cached sign-in artifacts in the browser, and then escalate only if the inconsistency is isolated to Copilot’s identity records.

References:

• I can't sign in to my Microsoft account