Dont know where to ask this question...

Ok first off,im not super computer savy so bear with me.Ive recently got a new computer and installed avast free version.It installs fine but when i try and launch it the dep doesnt allow it. ive gone in to dep settings and tried to exclude avast from dep protection but it doesnt allow me! ive seen other computers with vista run avast so i know it should work.i have vista ultimate,toshiba sat a215-s4767

Weird…are you sure you installed as ADMIN?

Did you use EMET (Enhanced Mitigation Experience Toolkit) to change DEP configurations?

I think the OP is talking about Data Execution Prevention (native Windows security feature, CPU related if supported) … this said I’ve it on for years but never saw it in action ;D

I know. And EMET is notorious for messing everything round related to DEP.