by default, the UCCX 5.x agent does not want to install on anything above windows XP. if you’re stuck on an older release of UCCX and need to install agents on windows 7 there is a way to force the install.

right-click the MSI file and choose troubleshoot compatibility. the wizard will run and should display “skip version check”, then proceed to start the install. option B is to edit the MSI file itself.

all this info came from:
http://www.lphelps.com/archives/2010/04/installing-cisco-agent-desktop-and-supervisor-on-windows-7/