>The fields in table ...dbf did not match the entries in the database.
>
>What does this mean and how can it happen and be prevented?

In addition, from the VFP Help file:

When opening a database-owned table, Visual FoxPro tries to confirm that each field of the table has a matching field object in the database.

The database or the table has been corrupted.
Use VALIDATE DATABASE to identify the problem.

The table being opened is the wrong one.
Remove and re-add the table to the database.