An internal error occurred on the report server

hi

I'm using custom authorization to check the access permissions of the user. In report manager i'm getting the error as "An internal error occured on the report server".

"The input stream is not a valid binary format. The starting contents (in bytes) are: 06-05-00-54-00-00-00-02-01-00-04-80-34-00-00-00-44 ..."

In Custom authorization i'm getting this error, Please help me in resolving this issue. If i'm using the Report server URL http:\\localhost\reportserver then its working fine. The problem is only with report manager. what might be the issue.

Regards

uday