Backup Problem

[enim]

Everytime I tried to backup hugh-massive data to external HDD, it stop at one particular point and pops-up message "The backup volume could not be found" and backups fails. I checked the integrity of file on which backup failed is perfect & OK.
Any suggestion?

[Case]

Such a message would alert me to re-check the connection between the computer and the external HDD.
How is the external connected? (USB1/USB2/USB3/FireWire/Thunderbolt/Ethernet/wireless/other)
What kind of Mac (please fill in the computer details in your profile)?
What kind (brand/model) of external?

Is this backup a few large files or hundreds/thousands of smaller files?
How far along is the copying before the interrupt? (beginning/halfway/near end)

How do you backup? (Time Machine/3rd party app/manual)

Some/all of the answers may be relevant to troubleshooting this.

[enim]

Thanks for your reply and help. I figured out and modify interupts - taps on sleepy goose which triggers with time machine. Tks!