James,

First of all I would suggest checking to see if any machines running this app have SMARTDRV on them. If so, either remove it completely or at the very least disable the write caching. I had this problem in the past and it never reoccured after this. Also, FoxPro's internal cache and SMARTDRV don't always get along well. Also, unless you have a backup or their is some utility I'm unaware of, those records are toast. HTH