hi,

I hope finds you well.

I have done migration process form exchange 2010 to 2013 and all the mailboxes moved smoothly after the movement there is some user face and issue.

that the outlook keep ask for the credential I tray to guess the problem when the outlook warm up the connection statues as you see in the below pic disconnected for the exchange directory

the email is running correctly (send - receive ) if cancel the credential box

and another thing in the account option I found in security tab  that the logon network security is selected as anonymous authentication

if I change it to negotiate authentication the message disappear and goes to connected  but we restart the outlook the option goes back  to  anonymous authentication  and the credential box will appear.

can you help us please

best regards .