Yeah, before running a service, it must be installed on the computer, Configuration Pannel -> Service, and you need administrator right to install / uninstall it, you can look the service already installed on your computer with regedit:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services

You might also want your service to use an NT account and his password, because your service will be running even if no one is logged, so if you use ADO (for example), you absolutely need registry key, and when no user is connected, no registry, error and, because a service, you don't know when it is bugged (except if you use custom log or the NTService logevent that write to NT log)

JeffB