Acronis Backup Cloud: Virtual Appliance backup fails with "Cannot find GXT item type 'mms::disk::disk'."

1. You deploy Acronis Virtual Appliance to a ESXi host and it appears in the Devices list in backup console.

2. You apply a backup plan to Acronis Virtual Appliance. 

3. Backup of Virtual Appliance fails with a 'Failed to execute the command. Resolving items to back up' error containing these messages:

| error 0x14b0015: Cannot find GXT item type 'mms::disk::disk'.
| line: 0xc8f602c2d30777ab
| file: k:/3602/enterprise/managers/gtob/gxt/common/items_by_type.cpp:95
| function: GetTypeInfo
| $module: agent_protection_addon_glxa64_3602