You can follow the TRiLOGI or WinTRiLOGI Help -> Upgrade menu and go to our website and download the Window Vista patch for the TLServer 2 to work with Vista.
Windows Vista is known to have compatibility issue with many engineering software. E.g. the MScomm32 that we use with XServer configuration and Visual Basic sample program all have problems working under Vista. So I would recommend that if you have a choice, then still use PC with Windows XP or earlier generation of Windows for less frustrating experience.