Outlook ask for credentials every minute

Hi @Coordinador Soporte Akros 

Thank you for posting your question in the Microsoft Q&A forum.   

I understand that some users in your organization are experiencing repeated password prompts in Outlook Classic, and that the issue persists despite clearing cache, reinstalling the app, and launching in safe mode. 

Since this behavior is affecting only a subset of users and you've previously been advised it may relate to certificates, I’d like to help narrow down the scope so we can identify the root cause more effectively. 

To help us investigate this further, could you please clarify a few details?  

1. Are they all on the same network or location? 
2. Do they share any common traits (e.g., same device type, OS version, Outlook build)? 
3. Do you manage certificates internally or through a third-party provider? 
4. Have there been any recent changes to your certificate setup or domain configuration? 
5. Does the issue occur only in Outlook Classic, or do other apps (e.g., Outlook Web, Teams) show similar behavior? 
6. Is there any pattern to when the password prompts appear (e.g., after sleep, restart, or network change)? 
7. Are there any specific error codes or messages shown when the password prompt reappears? If possible, could you share a screenshot or log snippet? 

Once we have this information, we’ll be in a better position to determine whether the issue is related to authentication, certificate trust, or something environmental. 

In the meantime, here are a few workarounds that may help stabilize the affected users' Outlook experience: 

1.Use Outlook Web Access (OWA) If the issue is isolated to Outlook Classic, users can access their mailbox via Outlook on the web. This avoids local authentication issues and ensures continued access. 

2.Remove Stored Credentials from Windows Credential Manager 

• Go to Control Panel > User Accounts > Credential Manager > Manage Windows Credentials 
• Remove any entries related to Outlook or Microsoft 365 
• Restart Outlook and re-authenticate 

3.Enable Modern Authentication (if not already enabled) If you're still using Basic Authentication, switching to Modern Authentication can resolve persistent credential prompts.

4.Check for Office Updates Ensure affected users are running the latest version of Office.  

5.Create a New Outlook Profile 

• Open Control Panel > Mail > Show Profiles 
• Create a new profile and set it as default 
• This can help bypass corrupted profile settings 

6.Temporarily Disable Add-ins

Even though you've tried safe mode, manually disabling all add-ins via File > Options > Add-ins and restarting Outlook may help isolate the issue. 

Looking forward to your reply so we can assist you further.

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