What about:

llError = .F.
lcOnError = On("Error")
ON ERROR llError = .T.
USE Customer EXCLUSIVE IN 0
ON ERROR &lcOnError

IF llError
   MessageBox("Could not pack, table in use...")
ELSE
   SELECT Customer
   PACK
   USE
ENDIF

HTH

---

>Is there a function that determines whether a table is in use.
>
>What I need to acomplish is:
>
>if table_not_in_use()
> select 0
> use customer excl
> pack
> use
>else
> wait window 'Could not pack, table in use...'
>endif