When selecting the disks for my Image Based backup I just want to backup the Windows server (C-drive) but Cloudberry also selects the Microsoft Reserved disk with 128MB size of the other (iSCSI) disks.
They are backed up in another job.....
Yes, system-reserved partitions are essential if you want to restore that system to another machine.
If there is no such need you can only select disk C: for that plan.