Its going to likely be data corruption or registry issues.
Do the following please
Click Start, type in %temp% and press enter
Delete all files and folders listed in the new window then restart
Then Download CC Cleaner (free) from hereCC Cleaner
(Click Download Latest Version on the top right)
Run it and let it scan and repair your registry.
Once done, restart the computer
Click Start, All Programs, Accessories, right click on Command Prompt and select Run As Administrator.
A black window will open.
Type in it
press enter and when it has completed, type in
It will complain the Volume is in use and to run on restart. Say YES and restart the computer
Than test and let me know if it still shuts down please