Description
Operating system error 21: drive not ready.
Common causes
A. The drive or printer being used is not ready: a USB drive or network drive was disconnected, or the printer is off or offline.
Common solutions
A. Reconnect the drive or turn on the printer and set it online, then retry.
Notes
BR stopped reporting this error in version 4.30. ACS 5 runs on a later BR release, so it should not appear in ACS 5. If it does, write down the program name and line number shown and call ACS.