1. find your CAPS LOCK key and stop using it.
2. Your error code is reporting: Locical Unit not ready. Manual intervention
required.
3. What device are you using? What firmware version?
4. What OS?
5. What version of the product are you using?

Chris

"MARK" wrote in message
news:3ce2a577$1@hronntp01....
>
> OUR BACK UP KEEPS ERRORING OUT WITH ERROR CODE # 05-20-23-00-0403
> THE DEVICE RECEIVED AN INVALID COMMAND. ANY SOLUTIONS ?