We have successfully migrated some of our users from Exchange 2010 to 2013 - the ones running Windows 7 and Office 2007 and Office 2013.

We have some users with Windows XP and Office 2007 though and when they start Outlook they get prompted to logon to the mailbox. These are all domain connected PCs in a single domain. If they put their details in Outlook opens as normal but the next time they start Outlook 2007 they get prompted again.

From looking around I suspect it is something to do with our UCC certificates.

The primary name is ourdomain.com

The alternate names are mail.ourdomain.com, mail2.ourdomain.com, ex2010.ourdomain.com and ex2013.ourdomain.com

I have tried setting EXCH and EXPR principal to ourdomain.com and the prompts remain.

Have we set the primary name wrongly ? Should it be mail.ourdomain.com ?

Any help appreciated

Darren

Windows XP is out of support, Microsoft doesn't test new technologies with oos platforms.

If you look around the web XP with any Office version has problem connecting to Exch 2013

For anyone who is interested I managed to get it working by running regedit on the problem PCs and changing this key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\ImcompatibilityLevel to 2

Now Outlook2007 goes straight in with no logon box.

• Marked as answer by Goobz 17 hours 5 minutes ago

thanks for sharing