error message warning error 025%ystem cmos checksum bad - default configuration used

Hello @Paula Benson

Thank you for reaching out to Microsoft Q&A and informed us about the error code. The error message 025%ystem cmos checksum bad - default configuration used indicate that it is a BIOS error and a dead or dying CMOS (Complementary Metal-Oxide-Semiconductor) battery, in order to fix it please follow these steps:

1. Restart your PC:

• Sometimes a simple reboot can fix the issue

2. Open BIOS/UEFI settings:

• When the error shows up, it would ask you to press a key to enter BIOS (F1, F2,....), press it
• Once in BIOS settings, do not change any settings for it could affect your PC settings
• Look for option that said Load Optimized Defaults (Load Default Settings) and select it > Exit
• Save and Exit

3. Change the CMOS battery:

• Locate the battery in your PC and carefully removed it and replace it with a new battery (CR2032 recommended) and boot your PC again

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