>>Thanks for your encouragment. So far the only commonality appears to be that the records are adjacent within the file, which makes me think, well, it could be a bad spot on the disk maybe?

Like Eric said, not a chance to cause cleanly deleted records. Trashed unreadable files, maybe.

Have you actually found the records marked as DELETED in the file, or did you confirm that they were NOT THERE AT ALL? -- big difference. If they are there marked deleted, find the places in your code that delete records in those files. If they are not there at all, I'd suspect duplicate keys allowing newly-added records to overwrite the old ones.

It worked fine for years and just recently started doing this? What else changed at the same time? New employee? Program corrections or additions?

Do you have an error handler that catches "file is in use" errors on an append blank? -- or do the users get "Cancel", "Ignore", "Suspend"? I once found that happening at a new client while users were adding new customers. They were choosing ignore, at which point the next line of code AFTER append blank would execute, REPLACEing new customer info into an existing customer's record. This sure sounds like that kind of problem, IF the records are not there in the file at all.

Good luck, and let us know what you find.