>>>>>>>>>>>>>>>>>>
Hi!

Try to take INV in query into '()' and add 'm' - for case if you have such field in current table (VFP takes field value even when memory variable exists).
In addition, put space before each semicolon, otherwise you risk to have even syntax error:
>>>>>>>>>>>>>

>STOR ALLT(THISFORM.INVNUMB1.VALUE) TO INV
>SELECT * ;
>FROM transactions!factgrostete INNER JOIN transactions!factgros ;
>ON Factgrostete.invnumb = Factgros.invnumb ;
>WHERE Factgrostete.invnumb = (m.INV) ;
>INTO CURSOR QUERY1

Actually the variable was already use as a fieldname in the header table and the field definition was boolean. I changed the variable to (m.inv_1) and it works. Sometimes the little cause the biggest headaches.