Quick Answer
Disconnect and reconnect both ends of your monitor cable, then run msdt.exe -id DeviceDiagnostic as admin.
Why This Happens
I’ve seen 0xC0261008 pop up most often when a monitor's EDID (Extended Display Identification Data) gets corrupted or when the cable is flaky. EDID is that tiny chunk of data your monitor sends to Windows saying “I’m a Dell U2415, 1920x1200, 60Hz.” When Windows can’t read it — boom, you get this error. It’s especially common with DisplayPort cables longer than 3 meters or cheap HDMI adapters. I once spent an hour chasing this on a coworker’s Lenovo ThinkPad because a dust speck on the HDMI port was breaking the handshake.
The error usually shows up when you connect an external monitor, and the display goes blank or shows “No Signal.” You’ll see it in Event Viewer under System logs, source Display, with event ID 0.
Fix Steps
1. Power Cycle Everything
Shut down your PC. Unplug the monitor from power. Wait 30 seconds. Plug everything back. This clears residual charges that mess with EDID.
2. Check and Reseat the Cable
Unplug both ends of the video cable (HDMI, DisplayPort, DVI). Inspect the pins for bent ones. Blow out dust from the ports. Plug it back firmly. If it’s a DisplayPort cable, make sure the locking tab clicks.
3. Try a Different Cable
If reseating doesn’t work, swap the cable. I’ve fixed this on Windows 11 machines by switching from a cheap HDMI cable to a certified one. For DisplayPort, avoid cables over 3 meters unless they’re active.
4. Run the Built-in Hardware Troubleshooter
Press Win + R, type msdt.exe -id DeviceDiagnostic, hit Enter. Let it find and fix driver or hardware issues. Takes about 5 minutes.
5. Update or Roll Back Your GPU Driver
Open Device Manager, expand Display adapters, right-click your GPU, select Properties. Go to the Driver tab. If the error started after a recent update, click Roll Back Driver. If not, click Update Driver – Search automatically. I’ve seen NVIDIA driver 531.18 cause this on RTX 3080s.
6. Force EDID Re-read
Open Monitor Settings in Windows (Settings > System > Display > Advanced display). If you see a “Properties for” section, click Display adapter properties. On the Monitor tab, check “Hide modes that this monitor cannot display,” apply, then uncheck it and apply again. This forces a fresh EDID read.
Alternative Fixes If the Main Ones Fail
Disable and Re-enable the Monitor Driver
In Device Manager, under Monitors, right-click your monitor and select Uninstall device. Reboot. Windows will reinstall the driver.
Use CRU (Custom Resolution Utility)
Download CRU from ToastyX. Run it, select your monitor, and delete any duplicate or corrupted EDID blocks. Add a standard resolution (e.g., 1920x1080) and restart the graphics driver via CRU’s restart64.exe. This fix saved me when a BenQ monitor’s EDID got corrupted after a power surge.
Check for BIOS Update
Some motherboards (especially ASUS B550) have buggy EDID handling. Check your manufacturer’s site for a BIOS update. For laptops, check for a firmware update for the display panel itself.
Prevention Tips
- Use quality cables. Cheap cables are the #1 cause of EDID corruption. Stick with brand-name HDMI 2.1 or DisplayPort 1.4 cables.
- Don’t hot-plug too often. Repeatedly plugging/unplugging an external monitor can corrupt EDID. Power down before connecting if you can.
- Keep drivers updated. GPU drivers from NVIDIA and AMD often include fixes for EDID handshake bugs. Use their official apps for updates, not Windows Update.
This error is annoying, but 9 times out of 10, it’s the cable. Start there.