I have uploaded here the IBM utility BACKUP.COM v.3.10. This 
version reportedly has corrected the error in v.3.00 which 
caused filed backed up to sometimes be irrecoverable due to 
its setting the size of BACKUPID.@@@ to 0. (Well, not 
irrecoverable, but not easily recoverable by everyone, and a 
nuisance to all.)

If you have PC-DOS 3.0, you should examine your file of BACKUP
.COM. If it dated 8-14-84, 8:00a, and is 5440 bytes long, it 
is almost certainly bad. In that case, you should replace it 
with BACKUP.COM from this file. 

This program is of no use to you unless you have PC-DOS 3.0 
and a hard disk. (Hopefully that means that you are a legiti-
mate recipient of this program.) Other DOSes do not have this 
particular bug.

I downloaded BACKUP.COM (because by Computerland dealer has 
not been swift in obtaining it for me, altho IBM has told him 
it is sending it to him--that it only does so for those who 
ask--can you believe that? Can you accept that?) from the 
Pacific Pallasides board, courtesy of Darryl Linkow, who 
conducts an AT conference there. The number is 213-459-6480. 
I've only been there twice, looking for AT/DOS 3.0 material 
(especially this program) but it appears to me to be a super 
board.