I've been trying to find a solution to a problem solved by installing SP2 for Office 2000/XP for machines that don't have the SP.
The problem is that in some cases Word documents do not display within Internet Explorer, usually when they are streamed by a servlet or CGI application, but display perfectly if downloaded directly through IIS5. The content can be saved locally and viewed, but never within the browser until the SP is installed!
Looking at the headers, the only differences seem to be the ETag and a missing "OK" from the status line (sent by Weblogic in my case). Is there some format in the ETag that Office is searching for or is the missing "OK" a problem??? Microsoft have no information available about this..