Suppose my local time is 6:15 AM but my PC time is showing 12.15 PM. If I change it manually to 6:15 AM, it sometimes will later change by itself to 6 hours advanced from my local time.
12 Answers
- Right click on clock in the notification area and select adjust Date/Time
- click change time zone button
- select your time zone and click OK.
If the minutes are correct but the hours are off, that points to a time zone difference.
If Windows is the only operating system, and it happened just once, the time zone could have gotten accidentally changed, and you can reset it as Zeeshan describes. If the change is recurring, there is more going on.
As Zeeshan suggests in a comment, the time may be set to synchronize with an external time standard. If so, it should do that all the time and the computer's time should be consistent. If it is repeatedly changing, there's more to the picture. The likely scenario would be that you are syncing with a time standard but haven't entered your time zone. The sync sets your clock based on a standard location and then you are manually changing the time. The next time it syncs, it gets "corrected" again. If you are syncing with an external standard, you need to specify your time zone.
There's another possibility if you are also booting Linux. In anticipation of Win 7 end-of-life, a lot of people are checking out Linux. If you are dual-booting Linux or trying Linux live sessions, it may change the time if you don't change a setting in Linux. Linux typically defaults to GMT and will keep resetting your clock when you boot it unless you set Linux for local time.
If the minutes change as well as the hours, that suggests a different problem. Running Win 7 suggests that it may be an old computer. The clock is maintained by a battery that typically lasts about 4-5 yrs. When that battery dies, the clock will keep resetting, and the time will be off by random amounts. If you haven't replaced that battery in a few years (or ever), look for a large button battery on the motherboard.
If the time discrepancies are random and the existing battery is at least three years old, just replace it. The battery is cheap, it's a simple fix that usually works, and even if that turns out not to be the cause, you would need to replace it soon anyway, and now you have a known good battery that will last for years.
