http://bugs.winehq.org/show_bug.cgi?id=26316
--- Comment #1 from Kenneth Robinette support@securenetterm.com 2011-03-09 10:19:34 CST --- (In reply to comment #0)
The current 1.3.15 version msi support does not remove the uninstall registry entry when a program is unistalled. This was fixed recently but is now broken again. When a progam is installed with a Microsoft .msi, an entry is placed in: hkey_local_machine\software\microsoft\windows\currentversion\uninstall If this entry is not removed, the program cannot be installed again. This requires a user to manually remove the registry entry.
I traced this problem to changes made to main.c of the unistaller program. If I use the main.c from the 1.3.12 version in the 1.3.15 version everything works as it should. Looks like someone made some 64 bit related changes and forgot to test the program!