Fix NS_E_WMP_NETWORK_ERROR (0XC00D11C0) in Windows Media Player

You're trying to stream a video from a network share or a web server in Windows Media Player. Maybe it's a movie on your NAS, or a training video hosted on a company intranet. You double-click, WMP opens, buffer spins for a few seconds, then pops: Windows Media Player cannot play the file because a network error occurred (0XC00D11C0). You check the file path, it's valid. Other players like VLC work fine. What gives?

This error means WMP couldn't complete the network connection or the file transfer was interrupted. It's not a corrupt file — it's a communication problem. The root cause? WMP relies on older Windows networking and internet settings that don't always play nice with modern firewalls, proxy configurations, or permissions.

Had a client last month whose entire accounting department couldn't watch training videos from a local server. Everyone got this error. Turned out their IT guy had set a proxy that WMP couldn't bypass. Took ten minutes to fix once I looked at the proxy settings.

Step-by-Step Fix

1. Check Firewall Rules

Windows Firewall or a third-party firewall might block WMP from accessing the network. If you're streaming from a local server (NAS, file share), make sure File and Printer Sharing is enabled for the Private network profile.

1. Open Control Panel > Windows Defender Firewall.
2. Click Allow an app or feature through Windows Firewall.
3. Scroll to Windows Media Player. Check both Private and Public boxes. If WMP's not listed, click Change settings then Allow another app and browse to C:\Program Files\Windows Media Player\wmplayer.exe.
4. Also ensure File and Printer Sharing is checked for Private.

If you use a third-party firewall (Norton, McAfee, Comodo), open its settings and whitelist wmplayer.exe or the network path.

2. Disable Proxy Settings in Internet Options

WMP uses Internet Explorer's proxy settings. If you have a proxy configured that WMP can't reach (like a corporate proxy that requires authentication), it'll fail.

1. Press Windows Key + R, type inetcpl.cpl, hit Enter.
2. Go to the Connections tab, click LAN settings.
3. Uncheck Use a proxy server for your LAN. If you must use a proxy, check Bypass proxy server for local addresses and add your network share's IP or server name under Exceptions.
4. In the Advanced tab of Internet Options, clear the Proxy Settings under Security section (if present).

3. Reset WMP Network Cache

Corrupted network cache can cause timeouts. Let's flush it.

1. Close WMP completely.
2. Press Windows Key + R, type %localappdata%\Microsoft\Media Player, hit Enter.
3. Delete everything in that folder. Don't worry — it'll rebuild on next launch.
4. Also go to %appdata%\Microsoft\Media Player and delete contents there too.
5. Restart WMP and try again.

4. Verify Network Share Permissions

If the file sits on a network share, WMP needs read access. It runs under your user account, so check that you have at least Read permission on both the share and NTFS (Security tab).

1. Right-click the shared folder, choose Properties.
2. Go to Sharing tab, click Advanced Sharing, then Permissions. Ensure your user or Everyone has Read access.
3. Go to Security tab, select your user, check Read & execute and Read are allowed.

One client had a server that required NTLM authentication but WMP wasn't passing it. Turned out the share was set to a different user group. Added their domain account — problem gone.

5. Disable IPv6 Temporarily

Some routers or network adapters have flaky IPv6 implementation. WMP sometimes prefers IPv6 and fails if the IPv6 path isn't fully working.

1. Open Control Panel > Network and Sharing Center > Change adapter settings.
2. Right-click your active network adapter, choose Properties.
3. Uncheck Internet Protocol Version 6 (TCP/IPv6).
4. Click OK, restart WMP.

If that fixes it, leave IPv6 disabled. If not, re-enable it — it's rarely the cause but worth testing.

What to Check If It Still Fails

• Network path test: From File Explorer, type the full network path (e.g., \\server\share\file.wmv). If you can copy the file, it's not a permission issue. If you can't, fix that first.
• Try the file in VLC: If VLC plays it fine, the problem is specific to WMP's networking stack, not the file or network itself.
• Check Windows Media Player version: Older versions (Windows 7 era) don't handle modern streaming protocols well. Update Windows fully or use an alternative player.
• Antivirus real-time protection: Some AVs (AVG, Bitdefender) scan network streams and block WMP. Temporarily disable real-time scanning (not just firewall) and test. If it works, add an exclusion for wmplayer.exe.
• Group Policy (corporate only): If you're on a company PC, your IT department might have blocked WMP network access via Group Policy. Check with them.

If nothing works, stop fighting WMP. Move the file to your local drive or use VLC, MPC-HC, or PotPlayer. They handle network streaming far better and won't give you this headache.