Clock Wrong
Microsoft Windows
Severity: MinorWhat Does This Error Mean?
Your PC's clock keeps losing time because of a dead CMOS battery or a sync problem. The CMOS battery is a small coin-sized battery on your motherboard that keeps time when the PC is off. Replacing it costs about $5 and fixes the problem permanently.
Affected Models
- Windows 11
- Windows 10
- Windows 8.1
- Windows 7
Common Causes
- The CMOS battery on the motherboard is dead and needs replacing
- Windows Time service is disabled or not syncing with an internet time server
- A timezone setting is incorrect, making the clock show the wrong time
- Malware is interfering with system time settings
- Dual-booting with Linux causes a clock conflict between the two systems
How to Fix It
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Right-click the clock in the bottom-right corner of your screen and choose Adjust date and time.
Make sure your timezone is set correctly — this is a common cause of the wrong time.
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Make sure Set time automatically is turned On. Then click Sync now.
This forces Windows to fetch the correct time from Microsoft's internet time server.
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If sync fails, press Windows + R, type services.msc, and press Enter.
Find Windows Time in the list. Right-click it and choose Start if it isn't running.
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If the clock resets every time you turn off the PC, the CMOS battery needs replacing.
It is a flat CR2032 coin battery. Buy one at any hardware or electronics store for about $5.
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To replace the battery, shut down the PC, open the case, and swap the old battery for the new one.
The battery is on the motherboard — it looks like a large silver coin. Note which side faces up before removing it.
When to Call a Professional
A dead CMOS battery replacement is easy and inexpensive. If you are not comfortable opening your PC, any repair shop can do it in minutes.
Frequently Asked Questions
Why does my clock lose time even with internet sync turned on?
The CMOS battery is almost certainly dead. Internet sync only updates the time while Windows is running. If the battery is dead, the clock loses time between shutdowns.
Can a wrong clock cause problems beyond just showing the wrong time?
Yes — a wrong system clock can cause SSL certificate errors in browsers. It can also prevent Windows Updates from installing correctly. Some apps that rely on timestamps may also behave strangely.
How do I know which battery type to buy?
Most desktop PCs and laptops use a CR2032 battery. You can confirm by looking at the battery already on your motherboard — the type is printed on it. Bring the old one to the store to make sure you get the right replacement.