Occasionally you run across the need to remove a Windows service when there isn’t a straightforward way to remove the software that installed it. The most frequent reason I’ve encountered is the installer that installed the service was run to install only under a specific user, and that user is not the person who wants to remove the service (this is bad — services should not be installed under a specific user).
Anyway, various forums have quite a few tools to help with the removal process, but none that I’ve seen so far come from Microsoft, and it makes me nervous to run randomly downloaded utilities on our servers. The best way that I’ve been able find so far is to remove the service from the registry and reboot the server.
Information about services on the local machine is stored a this location:
Locate the key for the service in question, delete it and all sub-keys and values, and reboot the computer. After that, the service should be gone.
This information courtesy of this blog post.