Well the same bug that was in CCleaner v3.09.1493 is still there in the new CCleaner v3.10.1525 portable.What the crap is going on with ccleaner never had the kind of trouble before with it. Guess I go back to the 3.08 version again.
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The thread tried to execute an invalid instruction
Someone get this info to the guy that makes the program.
The developers have told us before that they read all the posts, therefore they'll see this one. And with the good information you've supplied such as the CCleaner versions and Firefox version causing it they'll at least know where to look.