What is CSM-CONFLICT?
CSM-CONFLICT shows up as a medium-severity firmware fault. Compatibility Support Module (CSM) conflicts with UEFI OS or Secure Boot. It's also often linked to old OS installed in Legacy mode. See the troubleshooting steps below for the fix.
Common Causes
- CSM enabled with UEFI OS
- Old OS installed in Legacy mode
- Secure Boot + CSM conflict
Step-by-Step Fix Guide
-
1
Disable CSM for modern UEFI systems
Disable CSM for modern UEFI systems tends to be the quickest win here, addressing the most typical cause of CSM-CONFLICT.
-
2
Reinstall OS in UEFI mode
Should symptoms return, move on to the next steps — they're written specifically for harder-to-catch sw-bios instability causes.
-
3
Check Secure Boot compatibility
If earlier steps didn't help, "Check Secure Boot compatibility" directly addresses secure Boot + CSM conflict.
Commands & Diagnostics
No specific commands required for this error. Follow the step-by-step guide above.
Frequently Asked Questions
The leading cause of CSM-CONFLICT is CSM enabled with UEFI OS, though old OS installed in Legacy mode and secure Boot + CSM conflict also show up in our reports.
The fastest fix is "Disable CSM for modern UEFI systems". Only move on to the later steps if CSM-CONFLICT keeps coming back.
CSM-CONFLICT is a medium-severity issue. It can affect system stability, but the fix steps above typically resolve it without lasting damage.
Usually. CSM-CONFLICT is fixable with the steps above; a full Windows reinstall is rarely necessary unless everything else has failed.
Still Need Help?
Search our full database of 535+ documented PC errors for more solutions and step-by-step repair guides.
Search Error Database