Fix NS_E_BAD_BLOCK0_VERSION (0XC00D0063) – Step-by-Step

This Windows error means a disk's control block version is unrecognized. It's often caused by a corrupted boot sector or outdated firmware. Quick fix: run chkdsk, then update disk firmware.

Quick answer: Run chkdsk /f on the affected drive from an elevated command prompt, then update your disk firmware from the manufacturer's site. If that doesn't work, use DiskPart to clean and reformat the drive (back up first).

This error pops up when Windows tries to read a disk but finds a control block version it doesn't recognize. The control block is a small data structure at the start of the drive that stores metadata about the disk layout. When it's corrupt or written by a newer standard than your OS expects, you get NS_E_BAD_BLOCK0_VERSION. I've seen this on older drives that were used in another machine, after a power failure, or after a failed firmware update. It's not a death sentence, but you can't ignore it.

What triggers this error

You'll most likely run into this when you plug in an external drive, or when you're trying to use a disk that was previously in a RAID array or a different OS. The error message says "Disk %1 has unrecognized control block version %2" and it might appear in Event Viewer under System logs. Sometimes it happens right after a major Windows update changes how disks are handled.

Fix steps

Back up anything you can. If the drive still shows up in File Explorer, copy off critical files. If it doesn't, skip to step 2—your data might already be gone.
Run chkdsk from an elevated command prompt. Click Start, type cmd, right-click Command Prompt, and select Run as administrator. Then type:

chkdsk X: /f

Replace X with the drive letter of the affected disk. If you don't know which drive letter it is, open Disk Management (right-click Start > Disk Management) and look for a disk that's not showing a healthy status. After running chkdsk, you should see a message like "Windows has made corrections to the file system." If you get an access denied error, make sure you're running as administrator.

Check disk firmware. Go to the manufacturer's website (Seagate, Western Digital, Samsung, etc.) and search for your exact model number. Download the latest firmware update tool. This is the most common fix for this error because control block versions change with firmware revisions. After flashing new firmware, reboot and see if the drive is recognized.
If the drive still won't work, use DiskPart to clean it. This wipes everything, so only do this if you've exhausted other options. Open an elevated command prompt and type:

diskpart
list disk
select disk 1

Replace 1 with the actual disk number that corresponds to your problematic drive. Then type clean and press Enter. After that, create a new partition by typing create partition primary and then format fs=ntfs quick. This rebuilds the control block from scratch, which eliminates the version mismatch.

If the main fixes don't work

Sometimes the disk is physically damaged, and no software fix will help. Open the command prompt and run wmic diskdrive get status. If it returns anything other than "OK", the drive is failing. Replace it. Also, try plugging the drive into a different USB port or a different computer. I've seen this error only appear on one USB controller chipset, not the drive itself.

Prevention

Keep your disk firmware up to date. Check the manufacturer's site every six months or when you see a new version in their release notes. Also, avoid yanking out external drives without using the Safely Remove Hardware icon. That's a common cause of control block corruption. And if you're using an older drive with a newer Windows version, consider replacing it after 5 years—those old drives just can't keep up with the latest block versions.