What you probably want, can easily be accomplished using the
Task Scheduler API[
^]
You can use something like this
A New Task Scheduler Class Library for .NET[
^] to develop your solution in c# or just import the COM interfaces yourself.
The really easy solution is to use the
tools included with windows[
^].
Another benefit is that your solution no longer needs to be implemented as a service :) - it will be executed under the scheduler service, and will run even if there is no currently logged on user.
Regards
Espen Harlinn