I am currently in the proess of trying to upgrade from Office 2003 to 2007. For some reason some machines work without fault but some just keep saying "outlook must be online to complete this action ...". When I goto mail under control panel on the troublesome machine it says "Your exchange Server is offline".

I can Remote desktop to the server fine so I know its running. I can also connect to OWA. I have unchecked cached exchnage mode but that made no difference

All the machines are HP. The ones that don't work are DC7600 SFF (P/N: EC839ET#ABU) and the ones that do are HP DC7800 and HP DC7900 SFF.

Both are Windows XP SP3. Both are up to date with Windows updates (The DC7800/7900 seem to have a lot more office 2007 updates, I dont know why.)

Both machines have to cross domains to reach the email server, exchange 2003 (The server is on curriculum but the outlook is on Admin).

I believe there is a trust between the domains (unsure how to check).

After many hours of Internet searching I am at my whits end with it. I have even uninstalled both 2003 and 2007 and now even 2003 is giving the same errors.

Any help is appreciated.