>>Do you provide a completion routine for PBHOpenAsync? If not, then
you should be calling PBHOpenSync instead.



thanks.  Not sure what you mean by completion routine.

I have:

filename&=@gFileName$
DEF BLOCKFILL(PBlk&, 128,0)
& PBlk& +_ioNamePtr,filename&
% PBlk& +_ioVRefNum, gFileVol%
POKE PBlk& +_ioPermssn,_fsCurPerm
if out%=_false then FN FBwdToPBwd (PBlk&)     'this is the new line I added
ioErr=FN PBHOpenAsync(PBlk&)
LONG IF ioErr=0
    ioErr=FN FLUSHVOL(PBlk&)
    if ioErr=0 then ioErr=FN CLOSE(PBlk&)
XELSE
    [display error message]

I confess that I cookbooked it at the time - but it worked fine until the 
change to FB4.

Still trying to understand what the FBwdToPBwd function does, and why it is 
only necessary for some customers.

S