Hello,

We're using Infragistics Ultragrid ver 10.3 .  Some of our users have started receiving this error:

TheGrid DataError: Error text = Unable to retrieve cell value. PropertyDescriptor.GetValue call failed. This may happen for variety of reasons. One possible cause may be that the UltraGridRow's list object may be out of sync with the underlying data list. This can occur if the underlying data list fails to raise proper events notifying the bound controls (UltraGrid) of change in the data list. If you are using a custom IList data source, try implementing IBindingList interface on the data list and raising ListChanged event appropriately. If the data list already implements IBindingList then it may be failing to raise proper notifications. You can also try calling RowsCollection.Refresh on the grid's rows collection to synchronize the grid's list objects with the data lists. Note that the UltraGrid will continue operating normally.
TheGrid DataError: Exception type = NullReferenceException
TheGrid DataError: Exception = System.NullReferenceException: Object reference not set to an instance of an object.
at Infragistics.Win.UltraWinDataSource.UltraDataColumnPropertyDescriptor.GetValue(Object component)
at Infragistics.Win.UltraWinGrid.UltraGridRow.GetCellValue(UltraGridColumn column)
TheGrid DataError: No cell.
TheGrid DataError: No row.
TheGrid DataError: Source of the error is
TheGrid(_realTimeLocatesGrid_RealTimeLocatesView): Unknown.

Based on the user's logs, my suspicion is on this line of code: _grid.Selected.Rows.Clear() [I think its this line because in the user logs I can see the line before this has fired].  However this _grid.Selected.Rows.Clear() is wrapped in a try-catch block.  So my questions are as follows:

1. Could this line be causing a data error? I read that its due to the user trying to input a value? If the "Selected" property is null could it throw this exception?

2. As I've wrapped this bit of code in a try-catch, should it not go into the catch block?

3. What course of action should i take? rowsCollection.Refresh()?

I understand its an old version of Infragistics but we're not looking to upgrade as of now.  Really appreciate any help provided.

Thanks.