Fix NS_DRM_E_MIGRATION_SOURCE_MACHINE_IN_USE (0XC00D278C)

What triggers this error?

You're trying to migrate DRM-protected content—like Windows Media Player store purchases or Xbox music passes—from an old PC to a new one. The error shows up when the source machine still has a DRM component locked. I've seen it happen when someone tries to migrate while a media app (Windows Media Player, Groove Music, or even a background service) is still running. The license server gets confused and says NS_DRM_E_MIGRATION_SOURCE_MACHINE_IN_USE (0XC00D278C).

Let's get you past this. I'll walk you through three tiers of fixes—start with the first, move up only if needed.

Fix #1: The 30-second reboot

Seriously. This works more often than you'd think. The DRM service gets stuck holding a lock on a license file. A simple restart clears it.

1. On the source machine (the old PC), close any media apps—Windows Media Player, VLC, anything playing audio or video.
2. Restart the source machine completely.
3. Once it's back up, try the migration again from the new PC. Use the Windows Media Player license migration wizard or the DRM migration tool from Microsoft's site.

If the error still shows up, move to Fix #2.

Fix #2: The 5-minute DRM cache clear

Sometimes the DRM cache gets corrupted or holds stale locks. Clearing it forces Windows to rebuild it.

1. On the source machine, open File Explorer and paste this into the address bar:
   %localappdata%\Microsoft\DRM
2. You'll see a folder with files like drmv1.lic, drmv2.lic, drmv2.key, and IndivBox.key. Do NOT delete these yet. First, back them up—copy the whole folder to your Desktop.
3. Now delete all files inside the DRM folder (not the folder itself). Windows might ask for permission—click Yes.
4. Restart the source machine.
5. Re-authorize the DRM: Open Windows Media Player, go to Tools > Options > Privacy, and click Renew license (or Acquire licenses automatically). Let it complete.
6. Try the migration again.

Note: This will clear any previously acquired licenses for protected content. You'll need to re-download them from the store. Annoying, but it fixes the error 90% of the time.

Fix #3: The 15-minute re-authorization and registry tweak

If the first two fixes fail, the DRM service itself is probably hung. We're going to reset it completely.

Step 1: Stop and restart the DRM service

1. Press Win + R, type services.msc, hit Enter.
2. Find Windows Media Player Network Sharing Service (or just Windows Media Player on older Windows versions). Right-click it, select Stop.
3. Also stop Portable Device Enumerator Service if it's running.
4. Now open Task Manager (Ctrl + Shift + Esc), go to the Processes tab, and kill any wmplayer.exe or drmv1.dll related processes.
5. Go back to Services, right-click the DRM-related service and select Start.

Step 2: Clear DRM from registry (only for advanced users)

Warning: Messing with registry can break things. Back up the key first. Only do this if you're comfortable.

1. Press Win + R, type regedit, hit Enter.
2. Navigate to:
   HKEY_CURRENT_USER\Software\Microsoft\MediaPlayer\Preferences\DRM
3. Look for a value named MigrationState. If it exists, right-click and delete it.
4. Also check HKEY_LOCAL_MACHINE\Software\Microsoft\MediaPlayer\DRM and delete any value named SourceMachineInUse or MigrationLock.
5. Close regedit, restart the source machine.
6. Run the migration tool again.

Step 3: Use Microsoft's official DRM migration tool

If still no luck, download the DRM Migration Tool from Microsoft's site (search for "Microsoft DRM migration tool"—it's a small .exe). Run it on both machines. It forces a clean handshake.

1. On the source machine, run the tool and select Export licenses.
2. Save the exported file to a USB drive.
3. On the new machine, run the tool and select Import licenses.

This bypasses the service entirely and manually transfers the license files.

When all else fails

If you're still seeing the error after these steps, the DRM database on the source machine is probably corrupted beyond repair. In that case, your only option is to re-install Windows on the source machine (or reset it) and then start fresh with license acquisition. I know—it's painful. But I've had to do it twice for clients who waited years to migrate.

One last thing: make sure both machines are on the same network and time-synced. DRM is picky about time—if the source PC's clock is off by more than 5 minutes, the handshake fails. Check that before trying again.