ASP.NET MVC: Weird characters in error page

Question

Since I uploaded an updated version of an ASP.NET MVC 1 application to the server, the Yellow Screen of Death has changed to something like this:

��I�%&/m�{J�J��t��$ؐ@�����iG#)�*��eVe]f@�흼��{���{��;�N'���?\fdl��J�ɞ!���?~|?"��Ey�')=��y6����h���ͼhR��L�w�|��2=��Ez<����7�:5�<�+oy��:� �T����W�v�<[��~2�g�2��?�ʋ�y�hYՋ������t� _N���M�l�����{�,��Xn���Q�}�����*g�������7�� ~��j'u>K�{�IW4�>�U�w�|=-fYzR-���

When accessing pages with errors directly on the server via Remote Desktop (Windows Server 2008 R2, IE8), IE even tries to download the response but get's an error (message box).

Anybody encountered this before? Any idea how to solve this?

I also found this question, which seems to be very simliar, but unfortunately has not been answered by now: ASP.NET MVC app displaying weird characters

Answer 1

Most likely the screen you're showing is caused by GZip encoding in your code. You probably are applying a Response.Filter to the GZip/DeflateStream class and intending to encode your content, but then an error occurs and ASP.NET clears your Headers, but leaves the filter intact. The result is that your content is GZip encoded but the browser doesn't decode it because the Content-Encoding header isn't set.

To fix this add:

Response.Filter = null

into your Application_Error routine at the top to force any Repsonse filters to clear out.

Another thing that can screw you up is OutputCaching of GZipped content. If any OutputCaching is applied make sure you have the VaryByCustom option to allow for the different encoding types (none, Gzip, Deflate most likely).

+++ Rick ---