1. The problem might be a virus or defective hardware. I would try restoring the original factor settings, which would wipe out everything you put on the computer and restore it to the state when it was new. You may not want to do that if you have a bunch of stuff on your computer you want to keep like programs etc.
2. First, I would just shut down and restart the computer. Sometimes this is all that is necessary to restore any "lost" memory from Windows memory leaks. If that doesn't fix it, I would run a memory test to verify that all of the memory in the computer is working properly. After that, if there is still a problem, I would look for viruses or malware / other issues that are possibly sending deceptive messages to attempt to get one to buy security services, etc.
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