ExecuteCommand on Windows Service

[Steve C. Orr [MVP, MCSD]]

I have a windows forms app that interacts with a windows service that I
made.
My windows forms app can iteract with the windows service well. It can
start & stop the service, etc.
But one thing it cannot do is call the ExecuteCommand method of the windows
service.
I get an "access denied" error message when I try.
I've come to understand that the service must somehow have the correct ACL's
set to allow this. But I don't know how to set up the correct ACLs. I'd
like to do it programmatically if possible, but even a manual solution would
be better than nothing for now.

Any suggestions?

Thanks,
Steve

 

[Steve C. Orr [MVP, MCSD]]

Nevermind, I answered my own question. Google didn't fail me after all.
It wasn't an ACL problem.
The problem is that the "command" parameter that is passed to the
ExecuteCommand method must be a number between 128 and 256. (Other values
are reserved by the OS.)
Too bad the documentation doesn't mention such an important detail.