Cannot Create User Account

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I am trying to get my new linksys media center extender working but I
am hitting a snag. Communication between the devices is good and the
codes are all authenticated. However, when it gets to the "creating
user account" part it stops and says that installation failed. This is
almost certainly a Windows/Linksys software problem. Can anybody think
of a reason that the install isn't working?

I uninstalled all security software (anti- spyware, virus, firewall).
I also uninstalled the "windows media connect" program I have heard
some about. I am running an HP out of the box MC that I upgraded to
2005 via a CD HP sent to me.

Please help with any suggestions.

Thanks in advance.

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