The files ‘MyScripts.js’ and ‘CodeBehind.cs’ use a different language, which is not allowed since they need to be compiled together.
Both DataSource and DataSourceID are defined on ‘(id)’. Remove one definition.
This is an odd error message that usually means that you are binding a control twice to a datasource. However, if you are binding your control to an object (datatable, for example), that that object is empty and contains no data. Populate your data object and the error message will go away.
(I’ll post more as I find them…)