I cannot back up 2 clients

[Guest]

We used 5.0.238 to back up 4 Mac OsX clients.

Also, we are using 1 Mac OsX Server.

I scheduled back up at night.

Usually, I can see all 4 clients at working time.

 

At night, I can back up 2 clients.

I cannot back up 2 clients.

 

The error is below message.

"Cannot access volume Docs on K011235"

 

Sleep mode is Never at Energy saver for all clients.

Retrospect client is also ON.

All computer is same configuration.

 

I can see the computer on network after I wake up computer.

 

I don't understand why the clients didn't show on network at Retrospect.

I cannot find the problem.

Please let me know what is the problem.

[RonaldL]

You can see all 4 clients at working time, but have you tried backing them up? If you are able to backup during the day and not at night, something has to be happening at night. I would try turning off any screensavers and make sure the harddrive doesn't power down after a certain amount of time.

 

Where are the volumes you're trying to backup located? If they are located on external harddrives, the MacOS unmounts them if the user logs out of the machine.