BTW, and it's also possible that you have BACKUP files in place (perhaps from a test install)? In this case, the uninstall removes the original files and restores the backup files.
Backup log file items look like this:
|019|C:\yada\BACKUP\yada.0001
And make sure that your install writes the install file(s) action to the uninstall.log. You can open the uninstall .log with an ASCII text editor to check this.
Friedrich