Yamaha DGT7A Advanced Operation Manual page 89

In order to be copied, the destination disk must be the
same format as the floppy disk.
You must select the track you want to record before
recording.
Only E-SEQ files can be recorded onto an E-SEQ type
disk.
The disk may be damaged.
Press the Stop key to clear the message.
If this message appears frequently with other disks as
well, contact your nearest Yamaha service representative.
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