Data save and database updation in vb.net

I have to create a database application in VB.Net, but after displaying records by a datagrid or textbox, when i change any record and click save button then an error message is displaying. anyone can help me?.

code for saving is as follows:

clientsbindingsourse.endedit()
clientstableadapter.update(me.clientsdataset.clintmaint)