Chksum Error on startup

[TeresaM19]

Cheksum Error when desktop switches on - Googled the term and it relates to the battery..
Reinstalled Windows, but nothing seems to work

HP Support Assistant icon on taskbar shows messages waiting to be read, but not there when I open up the App.

Help and advice please

[Max3Aj · Accepted solution]

@TeresaM19, Hello and welcome to the HP Support Community!

Thanks for posting your question. I'm here to help you get things back on track.

I understand you're seeing a "Checksum Error" when your HP Notebook starts up, and that reinstalling Windows hasn't resolved the issue. Let's walk through what this means and how to fix it.
 

A BIOS Checksum Error typically indicates that the system's BIOS settings have been corrupted or reset. This is often caused by a failing or depleted CMOS battery (a small coin-cell battery on the motherboard that stores BIOS settings).

Step-by-Step Troubleshooting

Reset BIOS to Default Settings

Sometimes, simply resetting the BIOS can resolve the issue:

• Turn off the notebook.
• Power it on and immediately press the F10 key repeatedly to enter BIOS Setup.
• Once in BIOS, press F9 to load default settings.
• Press F10 again to save and exit.

If the error persists after reboot, proceed to the next step.

Replace the CMOS Battery

If your notebook is a few years old, the CMOS battery may be drained. Replacing it usually resolves checksum errors.

• The CMOS battery is typically a CR2032 coin-cell battery.
• For most HP notebooks, replacing it involves opening the back panel. If you're comfortable doing this, refer to your notebook's Maintenance and Service Guide on the HP Support site.
• If you're unsure, I recommend contacting a local HP-authorized service center. HP® Service Center Locator - United Kingdom | HP® Support

Update the BIOS (Optional but Recommended)

A BIOS update can help prevent future checksum errors and improve system stability.

• Visit the HP Software and Driver Downloads page.
• Enter your notebook’s model number.
• Download and install the latest BIOS version available.

Make sure your notebook is plugged into power and do not interrupt the update process.

HP Support Assistant Notifications Not Showing

This is a known issue sometimes caused by a corrupted cache.

Try the following:

• Right-click the HP Support Assistant icon in the taskbar and choose Exit.
• Open File Explorer and go to:
  C:\Users\<YourUsername>\AppData\Local\HP\HP Support Framework\Data
• Delete the contents of the Data folder.
• Restart your PC and launch HP Support Assistant again.

If that doesn’t help, consider reinstalling the app from HP Support Assistant Download - HP Support Assistant | HP® Support

I hope the information shared has been useful and resolves your concern.

Wishing you a smooth and hassle-free experience ahead!

If this solution helped, please click “Accepted Solution” so others can benefit too. Don’t forget to hit the “Yes” button if you found this helpful!

Warm regards,

Max3Aj

HP Support

[TeresaM19]

Thanks for replying.

This is an All in One PC - wary of opening it up.

I did mention to the support lady that rang me about replacing the coin battery, but she said there isn't one. 

Battery check report - no batteries installed.

I did the BIOS Reset to default settings - works after restarting, but leave it a few hours and the same fault happens.

Have an Extended Warranty - how do I book my PC in for a repair.

[Max3Aj]

@TeresaM19, Thank you for your response,  

I'm sending a private message to assist you with the next action. 

  

Please check your Private message icon on the upper right corner of your HP Community profile Next, to your profile Name, you should see a little blue envelope, please click on it or simply click on this link. 

  

I hope this helps! Keep me posted. 

  

Max3Aj

HP Support