Windows PopUp message: This operation has been cancelled due to restrictions in effect on this computer.

Symptom:
Running an app and getting a popup box titled "Restrictions"stating:
"This operation has been cancelled due to restrictions in effect on this computer. Please Contact yout system administrator"

Cause:
There is a restriction in the Group Policy.

Check:
Go to start -> run.
Type Edit Group Policy. Press enter.
In the Local Group Policy Editor, go to User Configuration-> Administrator Templates -> All Settings
Sort by State column by clicking on the heading.
Look at the enabled items, is "Don't run specified Windows Application" there? if not end here.
If it does exist then right mouse button click for the popup menu.
Select edit.
Find the options area, press the show button.
Investigate what each application does here and consider if it affects what you're trying to run.
I.e If mstsc.exe is there then Remote desktop wont run.

Resolution:
After determining the program to remove from the list:
If its the only one then select Not Configured. Thats it.
If theres several and you want to remove one application, then open regedit.exe.
Goto: HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explore\DisallowRun
Remove the application entry from there.