Request for the permission of type 'System.Security.Permissions.SecurityPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

I'm trying to run an asp.net 2.0 site through VS 2005 (I have the code stored on my file system).  The code runs fine until requests are made against excel.  The code bombs out at the last line of code below:

#Region "Set Heading"


'Outputs a DataTable to an Excel Worksheet

Private Function setHeading(ByVal oCells As Excel.Range, ByVal rpt As Go to the complete details ...