Alright, this is rather confusing for me. I have a plugin I'm writing for a shell replacement program called Aston. It sets the work area for the desktop. Now on the PC I first wrote it on (XP), it works fine. I copied it over to my 2kServer machine and SystemParametersInfo returns error 87 (incorrect parameter). I made a new project and tried the same thing and it works. The only difference is in the plugin the RECT (LPRECT in this case) is in a structure I created. Now, I sent the plugin to a friend of mine who runs XP as well, and his machine gave the same error. I've tried various things as copying the RECT in the structure to a RECT in the function and this didn't help either. I've made sure all the RECT variables are valid by converting it to a string (wsprintf) and MessageBox'ing it.
If any more information is needed I can give it.
Thanks in advance.