Can anyone point me in the right direction?

We have users on a satellite site, who are using Outlook 2003, then they are logging into Citrix to access the terminal server here, so that they can use the manufacturing system. When logged into Citrix, some of them can start a second Outlook session, others have to quit Citrix first, then log back in to Citrix and then open Outlook.

Given the outdated hardware, I'd prefer that all the users just worked over Citrix and didn't open Outlook (or anything) locally... But that is a longer term project.

I've tried googling and binging, but none of them are bringing up anything useful at the moment...

I've had multiple outlook-exchange sessions running no problem.

The only time it does like your issue is if they're using roaming profiles with mapped application data.

Yep, they should all have roaming profiles.

I think, possibly, one or two have somehow managed to get a different configuration. The local server on that site is a complete mess, with half the profiles on one drive and the other half on another... So it could be possible that the previous support company messed up somewhere.