blue screen on startup fatal system error c21000a

On start-up i seem to get this error i have contacted microsoft again and again and again finally they managed to help me pinpoint the problem to a ati radeon driver problem i am running win 7 professional 64bit they only way i can seem to get my laptop to start is by attempting to start up about 8 or 9 times it eventually works but is becoming very annoying and more persistant . I have found the driver on the toshiba website and tryed to install it , everytime i try this i get compatibility issues and cannot get it to work , if it make any diffrence i am on a toshiba satellite L300d-13S
can any1 help


Essential Member
What is the exact model of your Radeon card.

Also, go to Ctart > Run, and type smd.Now type sfc /scannow


model of ATI Radeon is 3100 Graphics


Excellent Member
Microsoft Community Contributor
What is the exact model of your computer again. I do not see the one you indicate. It might be country specific.

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