If you just finish Tenant to Tenant mailbox migration, you probably will run into issues with outlook reconfiguring the mailbox in outlook. Here are some a few solutions that will help in fixing the problem. Basically, the idea is to delete the previous login and outlook identities so that you can add the email again in outlook.
Solution 1 – Clear all outlook identities in windows registry. #
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\x.0\Common\Identity\Identities\
Solution 2 – Configure subkey in the registry #
HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Autodiscover
DWORD: ExcludeLastKnownGoodUrl Value: 1
Solution 3 – Clear all credentials #
1. Click the START button and type CREDENTIAL MANAGER then click on it
2. Click the WINDOWS CREDENTIALS TAB
3. Expand every item one by one and select REMOVE
Solution 4 – Delete License data #
Delete license data from location below
%localappdata%\Microsoft\Office\16.0\Licensing\
Solution 5 – Override ADAL WAM #
Run command prompt as administrator and execute commands below.
REG ADD HKCU\Software\Microsoft\Office\16.0\Common\Identity /v EnableADAL /t REG_DWORD /d 00000000 /f
REG ADD HKCU\Software\Microsoft\Office\16.0\Common\Identity /v DisableADALatopWAMOverride /t REG_DWORD /d 00000001 /f
