Windows 11 update causes external drives to disappear from backups

I can't confirm the exact cause of KB5124008 from here, but external drives that vanish after a Windows update are often a driver or USB power/detection issue, and it may not be the drive itself failing. 1. Unplug the WD My Book from the PC, wait 30 seconds, then plug it into a different USB port, preferably one directly on the PC rather than a hub. Use the original USB cable if you can. 2. Open Disk Management (press Windows key + X, then choose Disk Management) and check whether the drive appears there, even without a drive letter. If it shows as Unknown or Not Initialized, the PC sees the hardware but not the file system. 3. Open Device Manager, expand "Disk drives" and "Universal Serial Bus controllers," and look for a yellow warning icon. Right-click any problem device and choose "Uninstall device," then restart. Windows will reinstall the drivers automatically. 4. Check for Windows updates: Settings > Windows Update. Microsoft often releases fixes for update-related problems, so install any pending optional or cumulative updates. 5. To see if the update is the trigger, go to Settings > Windows Update > Update history > Uninstall updates and consider removing KB5124008 temporarily. Pause updates afterward, and check whether the drive returns. 6. Test the drive on another computer. If it doesn't show up there either, the enclosure or drive may be failing, so stop relying on it and copy any important files elsewhere. 7. Check WD's website for a drive utility or firmware update for your My Book model. If none of this works: contact Western Digital support with your model number, and Microsoft support if the drive only fails after KB5124008, and ask whether a fix has been announced for that update.