There have been some reports on problems using Windows Integrated Security from the Office plugin and I just wanted to share som info. that might be useful to you: The Office plugin relies on ServerXMLHTTP for its communication with the webserver and not wininet as Internet Explorer uses. ServerXMLHTTP has its own configuration utility for proxysettings, proxycfg.exe, which is run from the command prompt. ServerXMLHTTP tries to figure out if the webserver is reachable without going through a proxy, i.e. that it really *is* a local intranet server, before it gives away the logged on users credentials when using integrated security. If you experience "access denied"-problems connecting to the webserver it may be due to that ServerXMLHTTP fails to identify it as a local intranet server. If so, you may want to try run the proxycfg utility specifying explicit access for the server: proxycfg -d -p "" "www.episerver1.com;www.episerver2.com;" Naturally, you'll substitute www.episerver1.com and www.episerver2.com with whats appropriate in your environment. More information on configuring ServerXMLHTTP may be found here: http://support.microsoft.com/kb/291008/EN-US/ Best regards, Johan Olofsson Developer EP Research, http://r.ep.se