ObjectDataSource

hi
I have problem with the insert statement
Error description: The type specified in the TypeName property of ObjectDataSource 'InputtableObjectDataSource' could not be found.
It's the Inputtable_add.aspx and .cs fil
I also try to place all fils in the VS 2008.

In VS 2008 I have tried to configure Datasource but the following message come up:
ERROR massage in VS 2008:
>>The type 'Data.inputtablecontroller' from could not be loaded. If the type is located in the app_Code folder, please check that it compiles. If the type is located in a compiled assembly, please cheack that the assembly is referenced by the project.
Could not load type 'Data.inputtablecontroller' from assembly 'Microsoft.Web.Design.Client, Version 9.0.0.0, culture neutral, PublicKeyToken = b03f5f7f11d50a3a'<<