>How can I check to see if a disk has been inserted into the A: drive before I receive a system message?
>
>Thanks,
>Don Pollock

Try this:

Function Test()
Local lnError

* Initialize the flag
lnError = 0

* Trap the errors
ON ERROR DO ErrHand With ERROR(), @lnError

* Try to open an unexistent file just to trap errors
= FOpen("A:\XPTO.TXT")

If lnError != 0 && No errors, keep on working
...
EndIf

* The error handler follows...
Return