Scary Problem losing links to back end

[Eljefegeneo]

All of a sudden, I am losing links to certain tables on the back end. I have been making various changes to the forms as requested by the person who is testing the DB. This usually happens when they try to delete a record from the form and all kinds of error messages pop up across all the controls. Then when the form is closed a table disappears. And it doesn't even have to be a table that is data source on the form. So I try to re-link the table, but the "unlinked" tables do not appear when I check the box for "Always prompt for new locations". So I added the tables that are missing via External Data Link an access table. All is fine except when I try to re-link all the tables. Then it asks me where each individual table is located.
I do not panic; all I do is go back to the oldest version of the front end. But I am wondering why (1) I am losing links to tables and (2) why I am having such a problem re-linking them.
Any guidance as to how to avoid such heartaches would be appreciated. Why do the tables become unlinked? And when I try to re-link them to the new front end on which I have spent hours of work, I have to link each table individually?
[FONT=&quot] I am now making frequent backups of the new front end as I work on it so that I do not lose a whole day's or more work[/FONT]

 

[Galaxiom]

Are you and the tester working with the same copy of the front end?

 

[Eljefegeneo]

We are using the same front end, identical copies, but of course they are on different computers using the same front end. As I said, I save a copy on the server and anyone can copy the old FE to their desktop. The missing tables then appear. But when is copy both the front end and back end to a memory stick and then try to link them, the link table manager asks for each individual table's location.

The tester or I can be on the DB solo and it happens, so Ido not think it is a question of two user conflict.

 

[Galaxiom]

Have you tried importing everything to a new database?

 

[Eljefegeneo]

Will try that. For the time being, I am using the backup FE and only making changes to it on the FE copy I have on a memory stick. I can then update the FE to the folder on the server that can be copied to users desktops.

The question remains, why do links to tables disappear?