>It was recommended that to keep a grid from crashing when I delete the table's records and refill them with new ones... I should:
>- use COPY STRUCTURE to create a temporary file with proper structure
>- change the grids RECORDSOURCE to the new structure
>- change the grids columns CONTROLSOURCE to the new structure
>- change the delete the old source file and recreate the data
>- change the grids RECORDSOURCE to the recreated file
>- change the grids columns CONTROLSOURCE to the new structure
>
>How do you change the CONTROLSOURCE... I tried thisform.grid1.columns(1).controlsource= and I get an error of unknown item.

Well, you seem do too much..

With ThisForm.GrdData
   .RecordSource = ""
   .ColumnCount = -1     && Release all column objects, *notes
   Select Customer
   .RecordSource = "Customer"
   .Init     && If you give some proc on init to setting the grd, such as textbox, header...
   .Refresh
EndWith

*Notes: Once you change the GrdData.recordsource, all columns objects are auto-Reset.
i.e. any code on column, header, textbox will gone forever!

If you don't reset the columncount to -1, the column.width will follow old alias..
Of cos, most likely the layout width is wrong.

Now, reset everything and try to give all setting on INIT event.

For example:

* GrdData.Init
With This
For iX = 1 to .ColumnCount
   .Columns[iX].RemoveObject([text1])
   IF TYPE(.Columns[iX].Controlsource) = [N]
       .Columns[iX].AddObject([text1], [txtNum])   && self-numeric textbox class
   ELSE
       .Columns[iX].AddObject([text1], [txt])   && self-define own text, you can put code here.
   ENDIF
   .Columns[iX].text1.fontsize = 11
   .Columns[iX].text1.fontname = "Arial"
   .Columns[iX].text1.visible = .T.   && default visible value was .F. by Addobject()
EndFor
EndWith