>>In our big and Old VFP9 Application we Read data from SQL Server via SQLExec(), and show the Data in VFP – Grid.
>>Sometimes we have to Reload the Data and since Years this is done in this sequence:
>>- Reload the Data (sqlexec() ) into the same named Cursor as before.
>>- Remove the Grid (oGrid.release() )
>>- Create an New Grid Instance (newobject() )
>>And, also since years, we fight against C5 Errors…

Traditional answer would be that Remote Views avoid this issue altogether- but they're not always practical/flexible enough.

Theoretically you can set recordsource to "" before recreating the source cursor and the grid's layout should survive, but many of us have experienced blankings or other unstable symptoms from the event sequence or other unanticipated consequences- especially if focus is in the grid when this happens.

Which is why I'd strongly support Tore's advice wrt safe select, especially if you have complicated grids with careful widths and dynamic... settings. I did not know it was called "safe select" (learned something!) but this technique is widely used in our apps without C5 errors or infuriating visual anomalies.

Safe Select also makes it very easy to (for example) re-order by clicking header columns etc by simply adding an ORDER BY to the select. It's generic enough that you can create Resequence() and similar methods in your grid class and not have to look at it again for years at a time.