This site uses JS/XML/XSLT, and it works with no errors in chrome/safari/FF/IE8/IE7, when accessed remotely, but if I access the site through a VPN, I get an error that either a document element is lacking, or the XML is not well-formed, which it is. But this only happens with IE7 - the main browser we need working unfortunately.
Perhaps the client did something locally? but the xml/xsl files dont seem to be modified. I'm tearing my hair out over this.