You would need to dig the Update button in the EditCommandColumn by handling
ItemCreated and looking correct item (ItemType=ItemType.EditItem) then
column & controls for the LinkButton that is generated as the Update button.
After you have found it, set the CausesValidation to false for it.

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Teemu Keiski
MCP, Microsoft MVP (ASP.NET), AspInsiders member
ASP.NET Forum Moderator, AspAlliance Columnist
> Using VB.NET: I would like to disable causesvalidation (of a textbox
> and a dbcombo) when the user clicks the update button in the grid
> control of the editcommandcolumn. Please help.
> Thanks in advance,
> James P.