Halo trial-weird problem.

[alphaAI]

so.. when i was playing halo trial, i pressed Alt+F4 cause it was so laggy and stuff. Then when i clicked on the icon, it says "Fatal Error: There is a copy of Halo already running on this machine." What should I do??....

 

[mailpup]

Go to the Task Manager and close Halo then try restarting it.

 

[alphaAI]

It was already gone..

 

[alphaAI]

So, i tried re-installing, but it says they need to delete these all kinds of dll files tht get installed when u install halo trial. i tried deleting those, but i don't have permission to do it. i tried to change this security thing from the properties, but i don't think it really worked.