Random Deletions

Hi, I have a DB that is basically a big electronic form. Each table is a section of the form and the main central table stores the ID's from the other tables. Most of the relationships are one to one but without referential integrity because sometimes sections need to be skipped.

It's been growing fairly rapidly lately as bit's keep getting added but now a weird deletion problem has started appearing. Every once in a while when a user goes to complete the form (right at the end) it suddenly dissapears. The records in the related "section" tables are still there but the main table storing all the ID's loses the record.

There are NO cascade update/delete's on any of the relationships, also no-error message appears it just goes. I think there is a problem in actually saving the record because I moved a DoCmd.RunCommand acSaveRec command from the complete button to a slightly earlier process and the point at which the record dissapeared also moved.

Does anyone know what may be causing it? It only happens to about 1 in 30 forms and there is no obvious link between the problem and
a) the machine it happens on
b) the person using it
c) the data entered into the form

If it happens the same user can input exactly the same data in exactly the same way and it saves it fine.

It really is random!

People are starting to get really frustrated. I was tring to "sell" the idea to a new department as well and had 15 people sitting in front of a projector when it happened to me. I was mortified :eek:

Any ideas would be greatly appreciated.

thanks,

Tom