The other odd error is that I have is AJAX calls back to our server that fail to return all of the data. The HTTP header indicates one size for the data, and the actual text returned is considerably smaller, anywhere from only 10% to half, and even a few that returned 0 bytes. And this is after accounting for the fact that the data is UTF8 encoded. I have always assumed that if the AJAX call returns, and readyState property is 4 and the status is 200 then the data being returned should be correct, accurate, and complete. This error seems to be across all Internet Explorer versions and I've even seen it with Firefox. Has anyone seen any issues similar to either of these, or have any suggestions as to how to debug this?