What can cause a persistent “Reload the page to get source for” error in firebug?

Question

I\'m trying to debug the javascript of a specific page, and I keep seeing

Reload the page to get source for page.htm in Firebug.

On Chrome, I\'m

Answer 1

I got this message displayed while opening a page that had a content-encoding error. The page returned gzip compressed data, but a HTTP module corrupted the gzip content.