My computer keeps crashing!

Just as the title says, my computer keeps crashing. I have an illigitimate version of Win 7, but before it worked just fine. At the start up screen on the same screen its telling me to activate my product, it shows an error messsage saying "The instruction at 0x77b3lf19 referrenced memory at 0x00000008. The memory could not be read. Click on OK to terminate that program." I dont know if it has anything to do with the crashes, but maybe It'll help. This happened before, and all I did was physically clean the computer inside removing the dust, and it stopped crashing for a while. But now even after I did it again it keeps doing so. It does it at random times.
 
"I have an illigitimate version of Win 7"

We don't support "pirated" software in any way here...
 
"I have an illigitimate version of Win 7, but before it worked just fine."

No pirating, in case you didn't know its against the law.

" it shows an error messsage saying "The instruction at 0x77b3lf19 referrenced memory at 0x00000008. The memory could not be read."

This might be because it's an illegitimate version, so maybe if you bought the product it would work...
 
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