I did as you recommended booted in safe mode, ran Norton Virus Scan for the entire system, but my cursor still keeps jumping to the lower left hand corner, and occasionally clicking the Start button. Do you know what type of virus it might be in the Master Boot Sector? My Norton antivirus is a very basic version, so it might not be able to detect the virus. Any advice?
Hi, the jumping cursor while typing problem is a Boot Sector Virus issue. I fixed it by starting my Computer in Safe Mode F8, then doing a Virus Scan.
How I figured this out is when I reformatted my hard drive, the problem still existed; therefore the only place for the Virus information to hide was in the Master Boot Sector.
When You Virus Scan in Safe Mode, the Virus cannot Hide Itself from the Scanner. At least this one worked for Me.
After looking up this Pesky Virus problem on this Forum, I see almost 12,000 Posts relating to it! If this fix works for You, why not come back to this thread and say so, and/or share Your experience. Good Luck!

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