I have a GridView on an .aspx form and the content is controlled by an ObjectDataSource. The actual table update takes place in a .vb file. My question is now: how can I communicate a situation in the .vb file (e.g. no records found, missing update etc.) to the user of the .aspx file? In case of an error found in the .vb file, I want to put a message to the user in e.g. a label on the .aspx file.