Hi Jay,
You don't seem to be getting any replies so I thought I would be it another
try.

If you have a look at the DataViewSettings class in the help, it reads
"Represents the default settings for ApplyDefaultSort, DataViewManager,
RowFilter, RowStateFilter, Sort, and Table for DataViews created from the
DataViewManager".

I think the key word here is DEFAULT.

dataSet.DefaultViewManager.DataViewSettings[ dataTable ].RowFilter =
"Category = 'Cat One'";
DataView dataView = dataSet.DefaultViewManager.CreateDataView(dataTable);
// dataView.RowFilter matches the Category = 'Cat One' from above
dataSet.DefaultViewManager.DataViewSettings[  dataTable ].RowFilter =
"Category = 'Cat Two'";
// dataView.RowFilter isn't updated - it's still Category = 'Cat One'

So it seems DataViewSettings[ dataTable ].RowFilter is only read when
creating a new DataView.

Hope this is of some help.

Best Regards,
Phil.