how are you populating the grid?

the best way i've seen is to use create cursor and create a temp table that is the record source of your grid. then select records you want to display into another cursor and append them into the first... to clear the grid just zap the first cursor...to refresh it... zap the first cursor, reselect into the second and append into the first... alot of smoke and mirrors but your grid never loses its recordsource and should not come up blank...(1001 Things You Wanted to Know About Visual Foxpro pg. 180-181)

..also is your form using private datasessions? if so changing the data session can cause the grid to lose track of its record source...