I have a web setup project built using VS2008. I've converted my solution to VS2010 and now when I build my new installer and run the install from the MSI it installs fine, then at the last step, removes all the files it's just installed.
I have RemovePreviousVersions set to true. If I turn this off the files remain in place (but I get multiple instances in the Programs and Features in the control panel).
If I run the install again, the files reappear. From then on, the files always remain, even when installing another version. So, the problem seems to be with running an installer built using VS2008 and then running the same installer built by VS2010. The upgrade GUIDs on each installer are the same.
What is the cause and how can I fix this?