You mean it reboots the remote server that it is trying to backup. I have seen this issue with AOFO, because it tries to do the snapshot and reboots it while doing it if something wrong on vsp.sys.
Please try the below steps:
1> Try to do a backup without aofo option selected in the advanced open file option in the job.
2> What OS you have on this server. Check if you have the vsp.sys installed on that server.
To check vsp.sys -> click on run and type msinfo32 -> expand software environment and then system drivers. Go to the end and check if you see any vsp.sys
3> If you have vsp.sys then the best option is to uninstall the remote agent and install the remote agent again without having the aofo option selected. We can just remove the aofo but that sometimes gives issue.