NS_E_PROXY_ACCESSDENIED 0XC00D2EF6 Fix – Windows Media Player

Proxy settings are wrong – most common cause

What's actually happening here is that Windows Media Player (WMP) tries to use a proxy server that doesn't exist, or one that needs a login but WMP doesn't send one. This error happens a lot after you uninstall a VPN or a security suite like Norton or McAfee — those programs often set a system-wide proxy that sticks around even after they're gone.

On Windows 10 and 11, the fix is simple:

1. Open Settings (Win + I).
2. Go to Network & Internet > Proxy.
3. Make sure Use a proxy server is Off.
4. If it's on, turn it off. Also check Automatically detect settings is On.

The reason step 3 works is because WMP doesn't use your browser's proxy settings — it uses the system-wide proxy from Internet Options. If a leftover proxy address like 127.0.0.1:8888 is still there, WMP can't connect and throws 0XC00D2EF6.

If turning off the proxy doesn't help, open Internet Options (search for it in Start), go to Connections tab, click LAN settings, and uncheck Use a proxy server for your LAN. Then click OK twice.

Group Policy forces a proxy – corporate or school network

On a work laptop or school computer, the IT department might push a proxy via Group Policy. WMP then sees that policy and tries to talk to the proxy, but the proxy blocks WMP because it's not a browser — some proxies reject non-HTTP traffic from unknown apps.

To check if this is your problem, run this in a command prompt as admin:

gpresult /h C:\gp.html

Then open the generated gp.html file in a browser. Look under Computer Configuration > Administrative Templates > Windows Components > Internet Explorer > Internet Control Panel. If you see Make proxy settings per-machine enabled, then Group Policy is the cause.

You can't permanently remove a Group Policy proxy without admin rights. But you can bypass it for WMP alone. Open Internet Options again, go to Connections > LAN settings, and under Proxy server, click Advanced. In the Exceptions box, add *.microsoft.com;*.windowsmedia.com;*.wmp.com. WMP will then skip the proxy for those domains. It's a hack, but it works.

Firewall or antivirus is blocking WMP's port

Less common but real: a firewall rule or antivirus blocks WMP from reaching port 80 or 443 through the proxy. This happens most often with Bitdefender or Kaspersky when their web protection modules intercept traffic.

Test if the firewall is the problem by temporarily disabling it (disconnect from the internet first, unless you're on a trusted network). If WMP works with the firewall off, the fix is to add an exception for C:\Program Files\Windows Media Player\wmplayer.exe in your firewall's allowed apps list.

In Windows Defender Firewall:

1. Open Control Panel > Windows Defender Firewall.
2. Click Allow an app or feature through Windows Defender Firewall.
3. Find Windows Media Player in the list.
4. Check both Private and Public boxes, then click OK.

If you don't see Windows Media Player in the list, click Allow another app and browse to C:\Program Files\Windows Media Player\wmplayer.exe. Add it and make sure both networks are checked.

The reason this works is that when a firewall blocks WMP from reaching the proxy server's IP on port 80 or 443, the proxy can't even respond — so WMP gets the access denied error instead of a timeout.

Second fix for leftover proxy: registry cleanup

Sometimes the Settings app doesn't remove the proxy completely. The registry still holds the old proxy address. Here's how to clean it:

1. Press Win + R, type regedit, hit Enter.
2. Go to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings.
3. Look for these values: ProxyEnable, ProxyServer, ProxyOverride.
4. Double-click ProxyEnable and set the value to 0.
5. Delete the ProxyServer value entirely (right-click > Delete).
6. Close regedit and restart WMP.

Doing this manually forces Windows to stop using the proxy. I've seen cases where the Settings UI shows proxy off, but ProxyEnable in the registry was still 1. This is a known bug in Windows 10 22H2.

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