A critical error has occurred.Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
I solved this problem by changing the event name. There was two classes having same event name. Both class is used in two user control. And two user control placed on one page. This was creating problem. My System environment: Win Server 2008 R2 IIS 7 - 64 bit VS 2010 .Net 3.5