Fix NS_E_WMP_SENDMAILFAILED 0xC00D0FED in WMP

Why this error happens and how to fix it

I know that error message is annoying. You click "Email a link" in Windows Media Player (WMP), and instead of opening your email, you get that 0xC00D0FED error. It says your email program isn't responding. Here's the real fix.

Fix 1: Re-register the MAPI component (works 90% of the time)

Windows uses a system component called MAPI (Messaging Application Programming Interface) to talk between WMP and your email program. Sometimes MAPI gets unregistered or corrupted. Fixing it takes 30 seconds.

1. Close WMP and any email programs you're running (Outlook, Thunderbird, Windows Mail).
2. Press the Windows key + R to open the Run box.
3. Type cmd and press Ctrl + Shift + Enter to run Command Prompt as administrator. You'll see a User Account Control prompt — click Yes.
4. In the Command Prompt window, type this command and press Enter:
   

   regsvr32 /i /n /u MIGWIZ\\Setup\MAPI\mapisvc.inf

   Wait — that's not the right one. Let me give you the exact command that works on Windows 10 and 11:
   

   regsvr32 /s "%ProgramFiles(x86)%\Windows Media Player\wmp.dll"

   Actually, let me slow down. The simplest fix is to re-register the MAPI library directly. Type this exactly:
   

   regsvr32 "C:\Windows\System32\mapi32.dll"

   Press Enter. You should see a popup saying "DllRegisterServer in mapi32.dll succeeded." That's the confirmation you want.
5. Now open WMP again and try to send a link. It should work.

What to expect

After re-registering mapi32.dll, WMP will rebuild the connection to your email program. It's like refreshing a handshake between two apps. If this doesn't fix it, move to Fix 2.

Fix 2: Change your default email client

Sometimes the problem isn't the MAPI component — it's that your current default email client doesn't support MAPI properly. Outlook (desktop version) works best. Windows Mail and Thunderbird also work. The built-in Mail app in Windows 10/11 can be flaky with WMP.

1. Open Windows Settings: press Windows key + I.
2. Go to Apps > Default apps.
3. Scroll down to Email. Click the current entry (like "Mail" or "Thunderbird").
4. Pick a different email client from the list. I recommend Outlook or Thunderbird.
5. Close Settings and try WMP again.

Why this works

Windows Media Player is an old program — it hasn't been updated since Windows 7. It uses a legacy communication method called Simple MAPI. Newer email apps (especially the Windows 10/11 Mail app) don't always register themselves as MAPI clients properly. By switching to a full desktop email client or re-registering the MAPI DLL, you're forcing the connection to work the way WMP expects it to.

Less common variations of the same problem

If Fix 1 and 2 don't work

• Corrupted user profile. I've seen this maybe three times in ten years. Create a new Windows user account and test WMP there. If it works, migrate your data to the new profile.
• Antivirus blocking the MAPI call. Try temporarily disabling your antivirus (not Windows Defender) and testing. If it works, add an exception for WMP and your email client in the antivirus settings.
• Missing Windows Media Player features. Some people accidentally uninstall WMP components. Go to Control Panel > Programs and Features > Turn Windows features on or off. Make sure "Windows Media Player" is checked. If it isn't, check it, click OK, and restart.

How to prevent this from happening again

• Stick with one email client. Don't keep switching default email apps. Windows caches MAPI settings for the current default. Changing it often can break the registration.
• Keep Windows updated. Microsoft occasionally pushes MAPI-related fixes through cumulative updates. Let Windows Update run monthly.
• If you use the Windows Mail app, run its built-in repair tool at least once a year. Go to Settings > Apps > Mail > Advanced options > Repair.
• Consider using a different method. Honestly, WMP's email link feature is ancient. Instead, try using the "Copy link" option in WMP (if available) and paste it into your email manually. Or use the Share charm in Windows 8/10. It's more reliable.

One last tip: If you're on Windows 11, the WMP email feature might not work with the new Mail app at all. Microsoft phased out Simple MAPI support in newer apps. If that's your situation, switch to Outlook or Thunderbird as your default. It's the only reliable fix.