I'm not sure if this specific question has been asked, but I can't seem to find any viable solutions that are supported by Microsoft.
We have an office that currently has a few Windows Server 2003 systems configured with Terminal Services. Users in the office are on thin clients and log into their user accounts via RDP.
The PDC in this configuration also had Exchange 2003 Standard running.
I recently migrated their Exchange data to our Office 365 Exchange Online tenancy and configured each user's Outlook in their TS session. They have Office 2007 if this info matters.
The staff have complained of Outlook being very very slow to start and sometimes unresponsive for a period of time compared to their old on-prem Exchange.
The information I have found out by Google searching indicates that cloud hosted email with Outlook does not play nice in TS/RDS environments.
On the one full desktop computer in their office that I've set Outlook up on so it can be used outside of a RDP session everything is working beautifully. So I think the issue is the TS/RDS environment.
Why is that? Is it a Server 2003 TS and Outlook 2007 thing or is it the same for ALL iterations of TS/RDS and Outlook?
Microsoft recommends that if Outlook is to be used in TS with Exchange, that "cached mode" be disabled, but this won't work very well for cloud hosted email where it's going to be running everything by the cloud server over a slow internet connection.
What options do I have?
Best Answer
Office 2007 will shortly no longer be supported by Office365. Windows 2003 is very out of date and hasn't been supported for some time.
Therefore I would suggest that you build a test RDS with a more modern Windows Server and Outlook version and see if the problems continue. The startup delays are classic Autodiscover issues, but could also be something that is trying configure the Outlook client to point to the old server. A fresh environment and picking through the settings would be the best option.