constantly need to re-sign into outlook

Dear @Chris Rent Oxygen, 

Thank you for sharing your concern.  

To help me better understand the situation and assist you effectively, could you please share a few details such as:  

1/ Are you using Microsoft 365 apps installed on your computer, such as Outlook desktop, or Microsoft 365 apps on the web through a browser? 

2/ Does the sign in issue occur on both the desktop apps and the web version, or only on one of them? 

3/ What Microsoft 365 license is currently assigned to your account? For example: Microsoft 365 Business Standard or Business Premium. 

4/ What Windows edition is installed on your device? For example: Windows 11 Home or Windows 11 Pro.  

This will help me better understand the context and provide more targeted support. Any additional information will help me better understand and support you.    

In the meantime, you can try some steps below to verify the issue: 

Please make sure your operating system, Microsoft 365 apps and web browsers are fully updated before proceeding with any troubleshooting steps.   

Step 1: Check Microsoft 365 apps on the web 

This helps confirm whether the issue is specific to the desktop apps or affects the account itself. 

Open a web browser such as Edge or Chrome. 

Go to office.com > Sign in with your Microsoft 365 account > Select Apps > Open Outlook. 

Observe whether the web version keeps you signed in or also prompts you to sign in again. 

Step 2: Clear saved Microsoft 365 credentials in Windows 

Corrupted or expired sign in tokens stored in Windows can cause repeated authentication prompts. 

Close Outlook and all other Microsoft 365 apps. 

Open Credential Manager from the Windows search bar. 

Select Windows Credentials > Scroll to Generic Credentials. 

Remove entries that start with MicrosoftOffice16 or any Outlook or Office related credentials. 

Repeat the same steps under Web Credentials. 

Restart the computer. 

Open Outlook and sign in again when prompted. 

Step 3: Create a new Outlook profile 

A damaged Outlook profile can also trigger frequent sign in requests. 

This article provides further guidance on the topic: Create an Outlook profile - Microsoft Support 

Step 4: Check Conditional Access “Sign-in frequency” 

If this is a work or school account, your organization’s security settings may require you to sign in more often. A short sign‑in frequency policy can cause Outlook and other Microsoft 365 apps to repeatedly ask for sign‑in. 

Note: If you are an end-user, please reach out to your organization’s IT administrator to review Conditional Access or sign in frequency settings. 

As community moderators, we kindly ask for your understanding that our access to internal development details is limited. Our primary role is to guide users toward the appropriate resources and support channels. While we may not have visibility into performing deeper backend analysis, we’ll continue doing our best to support you within the scope of our responsibilities.  

I hope this information is helpful. If you have any questions or need further support, please don’t hesitate to reach out at any time. 

Thank you for your patience and understanding. 

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