Ahmad,

Try adding a new row to your child datarelation without using the datagrid and make sure it updates as expected.

>Hi Cathi,
>
>Sorry for the dealy, it's the situation here as you know...
>
>Well I am not using filter, I am using a DataRelation, and mostly I face this problem if the child table has no data to be displayed in the datagrid then when I add data to it & try to update the DA I got this error, some times if the child table has a data I don't see the error.
>
>I already tryed to set the .CurrentRowIndex, but no effect.
>
>
>
>>Ahmad,
>>
>>By chance are you using a filter? If so, then right before you change your filter, try setting the DataGrid.CurrentRowIndex to zero so it will not be outside the limits of the grid after the filter.
>>
>>
>>>Dear All,
>>>
>>>I am having a strange error:
>>>((An unhandled exception has occurred in your application. if you click
>>>continue, the application will ignore this error and attempt to continue
>>>if you click quit. the application will be shut down immediately.
>>>
>>>Index was outside the bounds of the array.))
>>>
>>>This error fires, when I add a new row to my data grid.
>>>
>>>Any idea what could be the problem?
>>>
>>>Thanks in advance.