Office 365, Email, Exchange, Outlook, How To Delete and Re-Add An Email Account in Outlook
How to remove and re-add an account from Outlook for troubleshooting purposes.
Please note that this will completely remove the selected email account from Outlook and delete the cached local copy of your mailbox, but items on the server will not be affected. These steps should only be taken after less drastic steps in troubleshooting an Outlook issue have failed.
Windows:
Removing your account:
See the following instructions from Microsoft.
Re-adding your account:
Mac:
Removing your account:
See the following instructions from Microsoft.
Re-adding your account:
Office 365, Email, Exchange, Outlook 2016/365 for Mac