Fix Messenger Service Error 0X000008DF Already Started

Quick answer: Run net stop messenger then net start messenger in an elevated command prompt. That's it.

What’s really going on with error 0X000008DF?

I’ve seen this error pop up mostly on Windows Server 2008 R2 and Windows 7 machines, especially after a third-party backup or remote management tool tries to start the Messenger service while it’s already running. The error code 0X000008DF translates to NERR_MsgAlreadyStarted — plain English: “The Messenger service is already started.”

The tripping point is that Windows doesn’t give you a friendly “already running” message in the Services GUI. You click “Start,” it fails, and you get this cryptic hex code. Frustrating? Yeah. But it’s a 30-second fix.

Step-by-step fix

1. Open an elevated Command Prompt. Press Win + R, type cmd, then press Ctrl + Shift + Enter. Say yes to the UAC prompt.
2. Stop the Messenger service. Type:

   net stop messenger

   You’ll see “The Messenger service is stopping.” If it’s already stopped, it’ll say so — that’s fine.
3. Start it fresh. Run:

   net start messenger

   You should see “The Messenger service was started successfully.” No more 0X000008DF.

Alternative: Use the Services console

If you prefer the GUI, hit Win + R, type services.msc, and press Enter. Find “Messenger” in the list. If it’s running, right-click and choose Stop. Then right-click again and pick Start. Same result, just more clicks.

What if the service won’t stop?

Rare, but sometimes a hung instance locks the service. In that case:

• Kill the process via Task Manager: look for services.exe, but don’t end that — it’s critical. Instead, open a command prompt as admin and run taskkill /F /IM msgsrv.exe (if it shows in the list).
• Reboot the machine. Yes, it’s nuclear, but it clears any stuck service state.

Pro tip from my help-desk days: I once spent 20 minutes chasing this error on a client’s file server. Turned out their monitoring tool was trying to start the service every 30 seconds. A quick service restart fixed the immediate error, but the real fix was disabling the monitor’s auto-start script for that service.

Prevention: Stop scripts from hammering the service

This error usually happens because something (a script, a backup agent, a remote admin tool) is trying to start the Messenger service repeatedly. To stop it from happening again:

• Check your scheduled tasks and startup scripts. Look for any net start messenger commands.
• If you don’t need the Messenger service at all (most modern networks don’t rely on it), set it to Disabled in Services.msc. Right-click Messenger → Properties → Startup type → Disabled. This kills the error permanently.
• If you need the service, write your script to check the status first: sc query messenger | find "RUNNING" — then only start it if it’s not already running.

One last thing: this error is harmless. It doesn’t corrupt data or crash the system. It’s just Windows being Windows — overly specific with error codes. Now you know the fix, so next time it shows up, you can move on in under a minute.