Bad Request HTTP Error 400. The request is badly formed

Bad Request HTTP Error 400. The request is badly formed.

I am getting this on a dev site. It only seems to be happening in IE as far as I can tell, very hard to debug.  Is dedicated server running windows 2008, don't seem to be having any memory issues.  Any ideas?


This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/10863-bad-request-http-error-400-the-request-is-badly-formed