Reset to see if this happens?
As to tracking it down, you start with the keyboard test, then move to a new user account and see if that follows it.
I believe there is some software package on my Win 7 machine that is generating data that appears as constant keyboard input. This only occurs on a system reset. Follow a reset, if I click on the logo on the lower left side of the desktop to open the 'search program and files', there is a constant flow of comma characters that fill the input box and keep going until a character is hit. This will not happen again until the next reset. I have done scans with my Norton Virus protection and my Malwarebytes Anti-Malware scanner and nothing is reported. With several hundred software packages loaded on the machine, I am not sure how to track down what is causing something to appear as if it is keyboard input upon a system reset. Unless it is really coming from some mis-reading of the keyboard that is only following a system reset.
Any ideas of tracking down this random bug. At first I was concerned that this could have been from some virus software but scans don't reflect that.

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