This article shows what to do if Outlook keeps asking for username and password. The most common cause is having old credentials stored in the credential manager. Open the Control Panel from the start menu.Overview
To clear the credential manager:
They will look like MS.Outlook:netid@usf.edu, or MicrosoftOffice15_Data:SSPI:netid@usf.edu.
If using Windows 8, right-click on the start button and select Control Panel.
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