When installing applications on multiuser environment such as a Terminal/Citrix server, you must put the server into install mode, either via the command prompt or using Add/Remove programs in Control Panel.
To put the server into install mode using command prompt type: change user /install
To put server back to execute mode after you’ve finished installing the app, type: change user /execute
When you install the application in Install mode, and information normally written to the HKEY_CURRENT_USER key will be written to:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install
This key is then copied back to HKEY_CURRENT_USER when the user logs on to the Terminal/Citrix Server.