Windows Mobile Center installation problems

I've got a HP iPAQ Windows Mobile based device. I use a Windows Vista Home
Premium computer. I experienced problems synchronizing my iPAQ (server busy
was the message I received) and decided to uninstall and install Windows
Mobile Device Center again. In the process something went wrong and now, when
I try to install again (I downloaded the latest version from Microsoft
website) I receive a message saying another more recent version is already
installed but there is no way to find and start the application.

On the other hand, when I try to uninstall adn install again, I find there
are two programs: the Windows Mobile Device Center, with no uninstalling
information and an update for the product. Everything is fine when I unistall
the update but an error message (there is no uninstalling information and the
machine cannot find the file wmupdate.msi) happens when uninstalling the base
program.

Any hint or ideas will be very much welcome.

Thanks a lot in advance.