How best to manually uninstall a program in windows 7/vista

I have a program whose uninstall program is giving me grief, it has an error partway through uninstall, stops and rolls back.

I would like to uninstall this product manually so what is the best way to go about doing this?

Revo Uninstaller is your best bet

With its advanced and fast algorithm, Revo Uninstaller analyzes an application's data before uninstall and scans after you uninstall an application. After the program's regular uninstaller runs, you can remove additional unnecessary files, folders and registry keys that are usually left over on your computer. Even if you have a broken installation, Revo Uninstaller scans for an application's data on your hard disk drives and in the Windows registry and shows all found files, folders and registry keys so you can delete them.

Completely uninstalls the program, and if it cant deletes all registry entries and files associated with that program

If you really want to uninstall manually, find the install log, usually in the application folder. It is a difficult to read plain text file that tells you what files where installed where and what registry keys were created. If the program you want to uninstall has a pretty simple install with not many actions reading it and uninstalling this way is not very difficult. There are potentially many caveats using methods other than the program's own uninstaller. The log file will not contain references to registry keys or files created by the program. There could also be files that are shared system files. Leaving a few files may be more unwanted than harmful. Many vendors uninstall programs do not get everything when they uninstall. Maybe it would be best to try looking for online support from the program vendor, or post the program, error and when you get it here and see if someone can help you run the uninstall successfully.