Hi!

>Hi
>
>On my customer table I have a integer key (u_key) which I use to link from my invoice header.
>

How you made that link? SET RELATION or something else?

>When I set up the relation and browse the tables using the IDE this works fine but when I try to use the link in a form it interprets this as the recno() and returns the wrong record.
>

If this is SET RELATION, is index properly set in the shild table to the key field index?

>Do I always have to convert the integer to a string to use it in a key???
>

RDBMS theory recommends to use only keys that uniquely number records. It does not matters what is a field type of the key, but Integer is the simplest, quickest and easiest way to oranize primary keys. Thus, why you expect VFP does not support this? :-)