Strange error message

[Mandi]

One of my users reports the following error frequently, only since changing my forum software to vBulletin.  Having never encoutered it myself, I am not sure where to start tracking it down.  The singular report makes me inclined towards a user browser or ISP problem, but figured I ask first

The server returned an invalid or unrecognized response.

TIA . . .

[Deb]

I see two suggested solutions for this on a quick search... let us know if either helps...

This is a known problem with Internet Explorer when accessing some secure sites. The problem should be eliminated by making the following small, one-time change to your browser settings:

On the Tools (or View) menu, click Internet Options

Click the Advanced tab.

Scroll down to the heading HTTP1.1 and uncheck both options that fall under it.

Quit and restart Internet Explorer.

The other area I see it brought up at doesn't seem quite like what we're looking for but I thought I'd mention it anyway.  This one is on Microsoft's support site at http://support.microsoft.com/support.../Q187/6/50.ASP

Deb
 - V2.0 comes complete with embedded finger-pointing

[Mandi]

Thank you very much !  It's probably also significant that she is still using 4.0 (discovered after my post) . . . I told her she might think about upgrading too.