Fixing Windows Media Player Authentication Prompts
Problem:
WMP sometimes displays auth prompts even though the logged-on user account is resolvable by ISA and has permissions to access the content through ISA policies.
Scenario:
ISA web proxy is configured for Windows Integrated authentication
ISA enforces authentication for HTTP traffic
WinMedia Player is configured to use a proxy (includes “autodiscover” or “browser”) for HTTP protocol
Discussion:
When WMP is acting as a web (CERN) proxy client, and the proxy requires Windows Integrated authentication, WMP will not auto-authenticate to the proxy if the proxy is specified as either FQDN or IP address. If the proxy is specified as NetBIOS (unqualified) name, WMP will auto-authenticate using the interactive account credentials. If the proxy requires Basic or Digest auth, an auth prompt is expected, regardless of how the proxy is specified. This behavior is the same if the proxy is obtained via an autoconfiguration (wpad) script.
By default, ISA 2004+ lists the proxies using their IP addresses in the wpad script. This default was chosen to prevent name resolution errors from impeding normal client-to-web proxy communications. While this works well enough for browsers, WMP “has issues” (yeh; we’ll go with that) when the proxy is specified using anything other than NetBIOS name.
Solution (two-part):
1. Disable the proxy settings for HTTP (pick one).
- Using WMP; Tools, Options, Network, Protocols, HTTP, set to “None”
- Using Regedit:
Key: HKCU\Software\Microsoft\MediaPlayer\Preferences\ProxySettings\HTTP
Name: ProxyStyle
Type: DWORD
Value: 0
- Using GPO; under “User Configuration\Administrative Templates\Windows Components\Windows Media Player\Networking”, set the “Configure HTTP Proxy” option to “Disabled”
2. Install the FWC from MS downloads http://www.microsoft.com/downloads/details.aspx?Fa...43da89
After making this change, the FWC will handle all HTTP requests from WMP and ISA authentication will now be satisfied through the FWC control channel instead of the HTTP protocol mechanisms. This will stop the random auth prompts from WMP.
Enjoy,
JimmyJoeBob Alooba (A.K.A., Jim Harrison)
HTH,
Tom
Ronald Says:
December 3rd, 2007 at 8:20 am
Dear Thomas,
Just want to know how i can block yahoo messenger on my ISA 2006. THANKS.
-rONALD
Jeff Overall Says:
December 6th, 2007 at 8:00 am
Another way around this issue is to simply add the domain name of the ISA array to the local intranet zone for Internet Explorer. This will allow WMP to send authentication packets.
Cheers,
Jeff Overall.
Adminaid.net » Blog Archive » Fixing Windows Media Player Authentication Prompts Says:
January 12th, 2008 at 2:01 pm
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