Troubleshooted a issue with outlook clients and Exchange 2013.
The internal Windows 7 clients with Outlook 2010 configued using autodiscover no problem but the XP clients would prompt for credentials and failed to authenticate.
I can across a Microsoft post that mentioned the reason was the certfificate’s primary name. To futher complicate the issue the company was using a wildcard certificate.
The exchange site’s name was mail.company.com (example) and the “*.company.com” certificate was ok. for the Windows 7 clients but not XP.
Set-OutlookProvider EXPR -CertPrincipalName:"msstd:*.company.com"
Did a iisreset and everything worked fine on both clients.
NOTE: On your CAS server, verify OutlookAnywhere / Authentication is set to Basic with SSL. May need to do IISreset to take effect immediately. Had to dumb it down for XP clients