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How to Fix CMOS Checksum Error

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The most common symptom of a failed battery is an incorrect or lagging system date and time in some types of BIOS, loss of BIOS settings when the computer is turned off, an error message when shutting down, etc. If the CMOS battery is still dead, the BIOS settings will be lost when the offending computer is turned off.

On Windows, CMOS stands for Complementary Metal-Oxide Semiconductor. This is any battery-backed memory that resides on a computer motherboard. The term also describes good storage technology that helps the Basic Input/Output System (BIOS) program on a single PC save important system data, including date and time settings, boot serial number, disk information, and other solution configurations.

If there is a problem with this type of memory, your computer will display this “CMOS Checksum Bad” error before the site starts Windows. In the guide, we will show you what causes this error and how to fix it.

What Causes CMOS Checksum Errors In Windows?

How do I fix the CMOS error on my computer?

Restart your computer. A biological restart usually generates an up-to-date checksum and clears the error.
Download and flash the BIOS update with it. Download the update from the manufacturer’s websiteRin’s fee, I would say.
Reset BIOS.
Replace CMOS battery.
Contact a laptop or computer repair technician or specialist.

“Checksum” describes a score (number or letter) used to control and verify the integrity of files on a storage device. When the CMOS memory values ​​get corrupted, you will get a CMOS Checksum Bad error on your amazing PC. It canIt cannot be caused by installing an incorrect and potentially corrupted BIOS update. The CMOS is only powered by a dedicated battery, so you can also often get a CMOS checksum error when the CMOS battery is low, bad, or old.

Power surges or improper unplugging of the computer can often cause a CMOS checksum error. Despite many causal factors, the specific “invalid CMOS checksum” is easy to fix.

Fun fact: CMOS is also known as Real Time Clock (RTC), COS-MOS (Complementary Metal Oxide Semiconductor Symmetry) or Non-Volatile Random Access Memory (NVRAM).

How To Fix CMOS Checksum Error

If the PC startup window displays a CMOS Checksum Bad error, the troubleshooting solutions listed below should resolve the issue.

Perform automatic repair

You can also use Startup Repair to fix issues that prevent Windows from starting correctly immediately after installation. Turn off the laptop and run withNext steps.

  1. When this PC is on, go to Settings > Update & Security > Advanced Startup > Restart Now.

If Windows does not start, turn off your device and turn it back on. When the screen turns on, press this F8 or F11 key several times, as a result, the advanced boot menu will appear on the screen.

Another way to fine-tune how the Start menu boots up is to wake your computer from sleep in three consecutive steps. Turn on the computer, or immediately press and hold the power button until the computer turns off. Repeat this a few times and your computer will want to load the extended boot menu on the third try.

  1. Select “Troubleshoot”.
  1. Select additional options.
  1. Select “Start Recovery”.
  1. Enter your account password and click Next. If your account is not password protected, leave the dialog blank and simply click Next.

The weapon will run diagnostics on your PC and fixnit any system problems that prevent it from loading properly. Reboot your computer when the job is done and see if the car restores the CMOS checksum.

Reset BIOS to factory settings

Performing a BIOS reset will erase all information stored in the CMOS. On the plus side, its presence will also remove corrupted data in addition to invalid BIOS values. How to access the BIOS and reset this task depends on your awesome motherboard and PC brand. For

For more information, check out some of our Windows-only BIOS reset guides. Make sure buyers restart their PC after resetting BIOS settings. This will rebuild the checksum values ​​or fix the CMOS error.

Press F1 or sometimes F2 on the error page, which will help you find the BIOS setup page and load defaults, load defaults, or any other assigned option to reset the BIOS to defaults.

Some computers may require you toPress another hard key (usually Del or F8) to display Windows BIOS setup information. Check the instructions on the page with the specific error to be sure.

What are the symptoms of a bad CMOS battery?

The laptop won’t boot.
You can hear the regular squeak of the motherboard.
The date and time have been reset.
Devices not responding are also known as not responding properly.
Hardware drivers should be gone.
You cannot connect to this Internet.

After exiting the error page, you can configure the BIOS from the advanced Windows boot menu. Turn off your computer and wait 20-30 minutes until it turns off completely on paper.

  1. Press the power button and hold your current F8 or F11 key while your main computer boots, just before our custom Windows logo appears on the home screen.
  2. Select “Troubleshoot”.
  1. Select additional options.
  1. Select UEFI firmware settings.Start=”5″>
  2. Click

The BIOS setup interface varies depending on the make of your PC. However, in the “Exit” field of the BIOS utility, you will find the option to permanently reset the BIOS settings.

  1. Go to exit, use the up and down arrows to move the selector to Load Defaults and pressshu input.

If people can’t find a way to reset BIOS settings to default, contact your PC manufacturer or refer to your device manual.

  1. Select “Yes” and/or press Enter.Start=”8″>
  2. Move

This will reset the BIOS settings of your Windows PC and running shoes to default. To make sure our own problem is solved, turn off your computer and turn it back on. If you keep getting a CMOS Checksum Bad error when you start your PC, try the next basic troubleshooting step.

Update BIOS

You need to update the BIOS if your PC’s BIOS version does not match the latest version on the manufacturer’s website (check “Driver Download” or “BIOS”). Download the BIOS utility containing the update for your PC model, use administrator rights and let the device automatically update the BIOS of your device. you

Before continuing, please be aware that the BIOS is usually aimportant component of your PC motherboard. Installing the wrong update and/or updating the BIOS incorrectly can damage your motherboard in the long run. Include the PC manufacturer’s instructions with your package to avoid damaging your device.

However, we strongly recommend that most users only download BIOS files from their preferred PC manufacturer’s website. Also make sure the BIOS update matches your PC model. The BIOS file of another device used on your PC is blocking the motherboard.

Finally, you should not shut down or restart your computer while updating the BIOS. Any obstruction (such as a power surge or crash) to operation can damage the BIOS or motherboard.

Replace CMOS battery

As mentioned earlier, your computer may not be able to verify the integrity of the BIOS files if a certain type of CMOS battery is dead. Signs of a new CMOS battery include incorrect information and time, unresponsive devices, connection problemsm to the Internet, etc.

If you do get a valid CMOS error checksum when trying to troubleshoot, the CMOS battery is most likely bad. Or, of course, he moved from his position.

Only try to reset or reset the CMOS battery if you are a particularly experienced computer person. Otherwise, contact your nearest repair center or contact the manufacturer of your current PC.

Check for physical damage

How do you reset the CMOS on a computer?

Turn off your computer.
Unplug your computer from the electrical outlet.
Press the power selector several times to discharge the capacitors.
Locate the CMOS battery on the system board.
Carefully remove the CMOS battery.
Wait every few minutes and then replace the entire CMOS battery.

Partial or possibly complete damage to the system board can also cause a CMOS Checksum Bad error. Take your computer to a repair center to check your company’s motherboard for damage.