I created a database to be used to conduct some surveys. There are three users in the database at one time, and about every 20 minutes, something happens that causes the database to lock, and I get an error message that says the database is unrecognizable. Then we all have to get out, I open it up, click "yes" that I want to repair the errors, then it works for a little while until it happens again. I have compacted and repaired the database every time after I make changes, so that is not it. Also, no one that is using the database is making any changes, they are simply entering data. Why is this happening, and how can I make it stop?