Which basically makes an unique field out of the adres and the same formula is in the table 'Adressen' and in 'EFOS' and with the lookup formula it adds the City in a third table but now the error says
"There was given a table with multiple values there where a single value was expected" roughly translated.
Any ideas on how to correct that ?
There are BLANK values in the colum Adressen[Plaats] so maybe that is the issue now ? (even though it never was before)