outlook.live login failure. See error message

The error details show HTTP status 503 with X-FEServer and esrc: StartupData, which indicates a transient server-side issue in Outlook on the web (outlook.live.com), not a problem with the local device or browser.

Recommended actions:

1. Treat this as a temporary service issue
   • HTTP 503 means the service is temporarily unavailable. In similar Outlook.com issues, access has resumed automatically after some time without any client-side changes.
   • Wait and try again later, especially if this started suddenly and other Microsoft services work.
2. Sign out of all Microsoft sessions
   • Use the global “sign out everywhere” option for the Microsoft account to clear stale sessions.
   • After signing out everywhere, wait some time and then sign back in to Outlook on the web.
3. Try a clean browser context
   • Open an InPrivate/Incognito window and sign in to outlook.live.com from there.
   • If that works, clear the browser cache and cookies for Outlook/Microsoft sites and retry in a normal window.
4. Check browser extensions and network
   • Disable ad blockers, VPNs, and other extensions, then retry.
   • If all devices on the same network see the same error, test from a different network (for example, mobile hotspot) to rule out local network interference.
5. If the issue persists for days
   • Because 503 with X-FEServer is a server-side condition, persistent failure over multiple days likely requires backend remediation.
   • Use the Outlook Forum on Answers or Outlook Tech Community to report the issue with the full error block (without personal data) so support and engineers can check the affected front-end server.

References:

• Outlook.com address returning TooManyObjectsOpenedError - Microsoft Q&A
• Can't log into Hotmail on Firefox anymore - Microsoft Q&A
• Not able to have access to my email ! - Microsoft Q&A
• Outlook and other apps are unable to connect to Outlook.com when using Basic authentication