[coleman]

Ah...sorry, I don't think I was fully understanding the issue at first.
Let me ask this, the new content server, does it support gzip where the old one did not? (I never paid attention if responses where gzip'd before).

The issue is that the IIS rewrite module can't rewrite if the http content is compressed. The suggested fix appears to be to filter the "Accept-Encoding" portion of the http request so that either the content is not sent to the proxy in a gzip'd form. So, I think if I could disable it in the server, it'd fix my issue, but it seems like as long as I can tweak the incoming request from the proxy so that the backend server(Calibre) doesn't send the content response back gzip'd, I'll be ok.

Thanks!