At the level of Win2k3 SP2 unpatched, sc.exe did not support the
sidtype parameter for setting a per-service SID. If you issue
sc.exe sidtype MyService Unrestricted
it spits out help text, then pauses for user input
Would you like to see help for the QUERY and QUERYEX commands? [ y | n ]:
At patch MS09-012/KB959454 (or maybe KB956572), if not before, sc.exe was upgraded to interpret this parameter. However...
If on 64-bit Win 2k3 with that patch, you run the 32-bit --
Program Files (x86) -- version, that will accept the
sidtype parameter and do nothing, at least on the various systems I've tested on.