You installed some other time setting software. But I can't be sure.
You may have to reveal more and tell us exactly what you mean by doesn't work and if you set the timezone on this machine.
Bob
My clock runs for about an hour. I have a Dell that runs Windows 7. This problem just started a few days ago. The clock will run for about an hour. I will try and correct the time and it will run for 45-50 minutes and reset to the time I set it to. It just does this continuously. It does not matter if I close my computer or turn it off or anything. It will will just run for a while and reset. Please help me! I can't figure out what is wrong. It is set to go off the government time. Please Help!

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