That sounds like a damaged OS. The sad news is that repairing Windows may not always be possible and then you have to find folk that will volunteer to help. I doubt system diagnostics will work if the OS is damaged or there are hardware issues.
Good clue, but it only confirms the machine needs work.
Bob
A few weeks back I noticed my clock wasn't keeping the right time. I clicked on the clock to update it and it said it could not open the file timedate.cpl file.Somehow the program to open the file got changed. I changed it to windows control panel and now it opens but still doesn't keep the time.I can synch it any of the settings and that works but only when the laptop is open. When I open the laptop it always has the time when I closed the laptop and the bios clock is the same way. I also have reset the bios clock with the same results.I have replaced the CMOS battery but till the same results.My next guess would be the motherboard. Is there a way to check the board? I have tried to run the system diagnostics but it always get jammed on the internal clock check at the 20% mark. Any ideas on this situation??

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