Microsoft Excel not allowing me to sign in

Kranti Potluri 0 Reputation points
2026-09-06T00:01:58.8033333+00:00

I have Microsoft Office subscribtion and it's been working fine. Not sure what happened all of a sudden now I am not able to save the files, and it says I have been logged out. And when I try to login it says "An unknown error has occurred. The error code is: 0x0"

Microsoft 365 and Office | Install, redeem, activate | For business | Other
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  1. Hani-Ng 1,130 Reputation points Independent Advisor
    2026-09-06T01:59:06.2833333+00:00

    Hi Kranti Potluri

    May I know whether you're using Windows or macOS?

    If you're using macOS, based on my research that Microsoft has documented a known issue where Office may display "Unknown Error 0x0" or "License Not Found" due to a licensing/activation problem. Microsoft recommends updating Office to the latest version through Microsoft AutoUpdate and ensuring the device is running macOS 12 or later. You can refer to this discussion: Error message 0x0 - Microsoft Q&A and see this article: Unknown Error 0x0 or License not found error in Microsoft 365 or Office running on macOS | Microsoft…

    If you're using Windows, here are some recommended steps you can try:

    • Sign out of Office and sign back in.
    • Clear Office credentials from Credential Manager.
      • Open Control Panel > Credential Manager > Windows Credentials
      • Remove entries related to Microsoft Office, Microsoft 365, OneDrive, or ADAL
      • Restart the PC and try signing in again
    • Run a Quick Repair, then an Online Repair if needed.
    • Verify your Microsoft 365 subscription is active.
    • Install the latest Windows and Office updates.

    I hope this information helps and look forward to your response.

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