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Can't sign in outlook Server Error: 401:undefined|undefined:undefined
UTC Date: 2025-07-10T00:19:57.157Z
Client Version: 20250620014.20
BootResult: fail
Back Filled Errors: Unhandled Rejection: Error: 401:undefined|undefined:undefined
err: Error: 401
esrc: StartupData
et: ServerError
estack: Error: 401
at Object.w [as createStatusErrorMessage] (https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.ad3a7e4e.js:1:1039)
at https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.ad3a7e4e.js:1:161561
st: 401
efe: KL1PR01CA0055
Sending, receiving, and organizing email in Outlook.com
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
I have the same issue, after chatting with support they informed me that it is a know issue and Microsoft is working on an update that should be live in about 1 hour. This is the page to view the report: https://status.cloud.microsoft/m365/referrer=serviceStatusRedirect
I really hope this will be solved soon.
Since this morning my hotmail is broken with the same error.
In several mail clients and the web outlook it's not working.
I can login to my account page, open Word, Excel Powerpoint Web but as soon as I try Outlook it fails.
And it seems to take MS way too long to fix this.
What a bad experience :-(
I’m having the issue too. Is it everyone having the same problem?
me to on thunderbird 070925 please help
Can't sign in outlook Server Error: 401:undefined|undefined:undefined UTC Date: 2025-07-10T00:19:57.157Z Client Version: 20250620014.20 BootResult: fail Back Filled Errors: Unhandled Rejection: Error: 401:undefined|undefined:undefined err: Error: 401 esrc: StartupData et: ServerError estack: Error: 401 at Object.w [as createStatusErrorMessage] (https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.ad3a7e4e.js:1:1039) at https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.ad3a7e4e.js:1:161561 st: 401 efe: KL1PR01CA0055
Same problem for me im afraid