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Dear Microsoft Support,
I am currently unable to activate or sign in to Microsoft Office 365 applications on my device.
Whenever I attempt to sign in or activate Office (including Word, Excel, etc.), I receive the error message I've attached.
Key observations:
This issue was already present before reinstalling Microsoft Office, and it still persists after uninstalling and performing a fresh installation.
Request: Could you please assist in identifying the root cause of this authentication failure and advise on how to resolve it?
It appears to be related to the authentication mechanism rather than a specific Office application.
Thank you for your support.
Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Locked Question. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
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Hi @Stefan Blom , I get this same error and its really annoying this message box popping up.
What is the solution to fix this without reinstalling my O/s or apps ?
Thank you in advance
Prax
@Prakash Somashekar Try an Online Repair, if you haven't already done so.
Exactly, I tried the Online Repair first, but it didn’t make any difference. In the end, I had to go with the classic Windows last-resort solution: Reinstalling the operating system from scratch ;)
no luck with the online repair or update.
@Prakash Somashekar, you can try reinstalling Windows, if you are ready for that drastic step. However, I would recommend that you start your own thread, so that your question gets more attention. Use the Ask a question option. (The current thread will be closed.)
Is this a business product? In that case, the local Microsoft 365 administrator in your organization should be able to contact Microsoft business phone support. See https://support.microsoft.com/en-us/topic/customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 .
Is this a business product? In that case, the local Microsoft 365 administrator in your organization should be able to contact Microsoft business phone support. See https://support.microsoft.com/en-us/topic/customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 .
Hi Stefan,
Thank you for your response. This was an issue I experienced on my personal computer at home.
After the technical support representative spent quite a long time trying to troubleshoot it, the suggested solution was to use Office tools through a web browser. Since I have long been used to working with Windows and wanted a more permanent solution, I decided to format the disk and reinstall the operating system, even though it meant reinstalling my applications.
That resolved the problem.
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I'm glad you got it sorted, although reinstalling the operating system is a rather drastic step (it is also time-consuming).