Hello @Anocha Yudhthonglang,
Thank you for posting your question in the Microsoft Q&A forum. I understand your inconvenience when facing this issue.
To understand your situation better, can you confirm this information about:
- Is your primary account a personal account (gmail, yahoo, hotmail,…) or a work/school account (has a company or school name)?
- If you use a work/school account, are you a Microsoft 365 admin in your tenant? For reference: How do I find my Microsoft 365 admin? - Microsoft Support
In the meantime, you can try these suggestions to check if they can resolve your issue:
Use Incognito/Private Mode
- Click the three dots (⋮) in the top-right corner.
- Select New InPrivate/New Incognito Window.
- Visit Outlook and try removing the account.
Try a Different Browser
You can try open OWA on another browser and remove the account again. Sometimes browser-specific issues can interfere with Outlook settings.
Clear Cookies and Cache
If you're using Microsoft Edge
- Click the three dots (⋮) → Settings.
- Go to Privacy, search, and services.
- Under Clear browsing data, click Choose what to clear.
- Select Cookies and Cached files, then click Clear now.
After doing any of these, go back to Outlook web, sign in, and try removing the external account again.
Please understand that our initial response does not always resolve the issue immediately. However, with your help and more detailed information, we can work together to find a solution.
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