On my Windows Server 2008 VPC several programs could not be installed by running the .msi file. Before starting the actual installation process, the Windows Installer checks how much disk space is available, but it doesn’t finish this process. It pops up with the message “please wait while the installer finishes determining your disk space requirements”, and after a few hours it still told me to wait. I’ve seen several posts on the internet about users with the same message, but nobody shows the reason why the Microsoft Installer can’t finish determining the disk space requirements.
By executing the msi via the command-line msiexec command, I can get passed that message on my VPC with enough disk space. Use the following command as a workaround:
msiexec /i filename.msi
See the comments for other suggested workarounds. I found a blog post that says that temporarily removing your VirtualPC Virtual Machine additions does the trick, see Donn Felker's "Cannot install programs on Virtual PC" blog post. It didn't work for me, but maybe it helps you.