You're using it incorrectly. The USED() function expects an alias name under wich table has been open not the table name. The AUSED() function can be used to get the list of aliases under which particular table is open or you can chec its return value to see if the table is open already or not.

>I do not understand this but it seems that the USED() function either has a bug in it and can't see that the file is already open, or...? Has anyone else dealt with this problem, or am I imagining this?
>
>

>*The CERTS table is already open.
>IF !USED("E:\PRODUCTION\DATA\CERTS")
>   * The program blows up right and says "file is in use".
>   USE E:\PRODUCTION\DATA\CERTS EXCLUSIVE IN 0
>ENDIF
>

>
>I don't think that the USED() function is working right, because if it were working right, it would not have gone into the IF !USED() condition.