Any attempt to increase Acronis Secure Zone fails with "Cannot change the size of Acronis Secure Zone to the specified values. Specify another size and try again."
Acronis Backup & Recovery 10 asks for a reboot to increase, decrease or create Acronis Secure Zone, or to restore partitions
This article describes how to deal with the situations when the Virtual Appliance backup/replication performance is low
You need to have unallocated space on the disk with the partition the size of which you intend to increase