Troubleshooting6 min read

Laptop Keeps Resetting the Date and Time, or BIOS Settings Not Saving? Causes and Fixes (Navi Mumbai)

If your laptop keeps showing the wrong date and time after every restart, or BIOS settings you've changed — boot order, Secure Boot, fan mode — don't stick after a reboot, the cause in almost every case is a dying CMOS (or RTC) battery, the small coin-cell battery inside the laptop that keeps the clock running and BIOS settings stored while the laptop is switched off or unplugged. It's a separate, much smaller battery from the main lithium-ion pack that runs the laptop itself, and it typically needs replacing once it runs down — usually after three to five years, sooner if the laptop often sits unplugged for long stretches.

This is different from a clock that slowly drifts by a few minutes over weeks, which is usually a Windows time-sync setting rather than a hardware fault. The clearest sign of a dying CMOS battery is a laptop that resets to a default date (often a date years in the past, whatever the BIOS firmware shipped with) every single time it's fully powered off, restarted after being unplugged, or after the main battery itself runs completely flat.

Why does my laptop keep showing the wrong date and time?

Every laptop and desktop has a small coin-cell battery (commonly a CR2032, though laptops often use a soldered or connector-mounted version of it) dedicated to one job: keeping the real-time clock ticking and holding BIOS/UEFI settings in memory whenever the laptop has no power from the wall or the main battery. When that battery wears out, the clock loses power the instant the laptop is unplugged and the main battery is removed or depleted, so it falls back to a default date baked into the firmware the next time it starts.

The giveaway is consistency: if the date and time reset to the exact same default value every time, rather than drifting randomly, that's the CMOS battery, not a Windows bug. A laptop that's three or more years old, or one that's been left completely uncharged and unplugged for weeks (common with a laptop that's been stored away), is the most likely candidate.

Is this the same as my laptop's main battery dying?

No — these are two completely different batteries doing two different jobs. The main battery is the large lithium-ion pack that powers the entire laptop, screen, and keyboard while unplugged; the CMOS/RTC battery is a tiny coin cell (or a small battery pack the size of a coin) that does nothing except keep the clock and BIOS memory alive during the brief moments the laptop has zero other power source. A laptop can have a perfectly healthy main battery and still show the wrong date every reboot, because the two circuits are entirely separate.

This also explains why charging the laptop longer doesn't fix it: charging tops up the main battery, not the CMOS battery, which only gets replaced, not recharged, on most laptops.

Why do my BIOS settings (boot order, fan mode, Secure Boot) keep resetting too?

The same battery-backed memory that stores the clock also stores BIOS/UEFI settings — boot order, Secure Boot, virtualization toggles, fan curve profiles, and more. When the CMOS battery is too weak to hold a charge, both the clock and these settings reset to factory defaults every time the laptop loses main power, which is why office laptops that have had boot order or Secure Boot carefully configured for a specific setup (dual-boot, a company imaging process, a VPN requirement) suddenly need reconfiguring after every full shutdown.

If only the clock resets and BIOS settings hold fine, the cause is more likely a Windows time-sync issue than the CMOS battery — worth ruling out before booking a repair, since it's a free, two-minute check covered next.

Could this just be a Windows time-sync setting instead of a hardware fault?

Yes, and it's worth checking first since it costs nothing. Open Settings, then Time & language, then Date & time, and confirm "Set time automatically" is switched on and that Windows is successfully syncing (there's usually a "Sync now" button). If the laptop has internet access and this setting is on, Windows should correct a drifted clock within seconds of connecting — if it doesn't, or the date resets to a clearly wrong default (not just a few minutes off) the moment the laptop is unplugged, that points back to the CMOS battery rather than a software setting.

A laptop that's connected to a workplace domain or managed by office IT policy can sometimes have automatic time sync blocked deliberately, which looks identical to a CMOS fault from the user's side — if this is a work laptop, it's worth checking with IT before assuming hardware is at fault.

Can wrong system time cause other problems, like login or VPN failures?

Yes, more often than people expect. Many security systems — VPN connections, two-factor authentication codes, website certificates, even some antivirus definitions — rely on the system clock being accurate to within a few minutes, and a laptop stuck on a default date years in the past can cause VPN logins to fail, 2FA codes to be rejected as expired, or websites to show certificate errors claiming they're not yet valid. For anyone using a laptop for wfh setup or office work, a resetting clock isn't just a cosmetic annoyance — it can quietly break the exact tools remote work depends on.

If you've noticed login or VPN failures alongside a wrong date, fixing the clock issue first is worth doing before troubleshooting the VPN or login problem separately, since a huge share of those cases turn out to be the same root cause.

Getting a dead CMOS battery replaced at your doorstep in Navi Mumbai

On a desktop, the CMOS battery is a simple coin cell that pops out and back in within a minute. On a laptop, it's usually a small battery on a connector cable tucked under the keyboard or motherboard rather than an easily accessible slot, so it needs proper disassembly rather than a DIY attempt — not a difficult repair for a trained engineer, but an easy way to damage a ribbon cable or clip if attempted without the right tools.

A Snapfix engineer confirms whether it's genuinely the CMOS battery or a Windows time-sync setting at your home or office anywhere in Navi Mumbai — Vashi, Nerul, Belapur, Kharghar, Airoli, Ghansoli, Kopar Khairane, Sanpada, Panvel, Seawoods, and Turbhe included — after a flat ₹499 on-site inspection (₹799 outside the current offer), and replaces the battery on the spot with a fixed quote agreed first. Across more than 10,000 devices repaired, this is a quick, low-cost fix that also restores any BIOS settings that kept resetting alongside the clock, backed by up to a 180-day (6-month) warranty.

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Common Questions

This is almost always a dying CMOS (RTC) battery — a small coin-cell battery separate from your laptop's main battery that keeps the clock and BIOS settings alive when the laptop has no other power. Once it wears out, usually after three to five years, the clock falls back to a default date every time the laptop is fully powered off.

No. The main battery powers the whole laptop while unplugged; the CMOS battery is a separate, much smaller coin-cell battery that only keeps the real-time clock and BIOS memory alive. A laptop can have a healthy main battery and still show the wrong date every reboot because the two are unrelated.

Yes. VPN connections, two-factor authentication codes, and website certificates often rely on the system clock being accurate, so a laptop stuck on a default date can cause VPN logins to fail or 2FA codes to be rejected. Fixing the clock resolves a surprising share of these cases.

Check Settings, then Time & language, then Date & time, and confirm "Set time automatically" is on. If the laptop has internet and still resets to a clearly wrong default date the moment it's unplugged — especially if BIOS settings like boot order reset too — it's the CMOS battery, not a Windows setting.

On a desktop it's usually a simple coin cell you can swap yourself in a minute. On a laptop, it's typically tucked under the keyboard or motherboard on a connector cable rather than an accessible slot, so it needs proper disassembly — best left to a trained engineer to avoid damaging a ribbon cable or clip.

Yes. A Snapfix engineer confirms the cause and replaces a dead CMOS battery at your home or office anywhere in Navi Mumbai after a flat ₹499 on-site inspection (₹799 outside the current offer), with a fixed quote agreed first and up to a 180-day warranty on the repair.