When trying to activate my Windows Vista installation recently, I was receiving an error code 0x80072F8F. My computer’s cmos battery is old and so when I unplugged my computer it caused my bios date to get messed up.
To fix this activation error, all you have to do is update the time/date to the correct time/date on the date indicator at the bottom right of the task bar. That’s it… once this is done you can try to re-activate. In my test, I didn’t have to reboot my machine luckily.
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