I have a grid with enough records to cause the vertical scroll bar to appear.  Some of the cells in a particular column are set to read only.  When I scroll, the read only cells change and different cells end up being read only - it seems to randomly apply the read only to different cells in the column.

I set the individual cells to read only like this:
CellValuePresenter cvp = CellValuePresenter.FromCell(((DataRecord)myXamDataGrid.Records[rowIndex]).Cells[columnName]);
cvp.IsEnabled = false;
cvp.Background = Brushes.Red;

Is there another way I can set indivdual cells to read only?  Or, are there any settings I could alter to prevent this issue from happening?  I tried different ScrollingMode and RecordLoadMode settings but the problem didn't go away.

Thank you,
Mike