Windows Media Player Vista--error message C0011BB

I think this question has been discussed but I am still having issues with
this. I cannot get live video and audio feed on the websites I go into. This
is the error message I get...You've encountered error message C00D11BB while
using Windows Media Player. The following information might help you
troubleshoot the issue.

Cannot play the file
Windows Media Player cannot play the file because the specified protocol is
either not supported by the Player or not supported by the server.

If you encountered this error by clicking a link on a Web page, the link
might not be valid.

If you encountered this error by typing a Uniform Resource Locator (URL) in
the Open URL dialog box, try opening the file by using a different transport
protocol (for example, "http:" or "rtsp:").

Can you please help me out? There was a post about reregistering something.
I did not understand it. If you can give me step by step instructions I would
really appreciate it. Thank you.

--
rpt