This might also be relevant:

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Then, in the Grid grdOffTruck.BeforeRowColChange method I have:

**update any changes made in grdOffTruck
select lvOffTruck
IF !TableUpdate(2, .T., ALIAS(),aSaveErrors)
WAIT WINDOW "Unexpected problem with " + ;
ALEN(aSaveErrors,1) + " records"
ENDIF
dodefault()
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