Error during transfer: "Item with the same key has already been added" (4042957)

Resolution

To verify that this is really the case, please perform the following:

- Open Core console and click on the agent name
- In the browser address bar, write down long GUID which is ID of the agent
- Open regedit
- Navigate to HKLM\Software\AppRecovery\Core\Agents\{GUID}\AgentProtectionConfiguration\ProtectionGroups
- Each protection group is numbered, starting from 0
- Expand each protection group number\VolumeNames and check under each number (partition) the value of LastDriverID

Values of LastDriverID should be unique and should not match each other. Same value of LastDriverID is a reason behind the error during the transfer. Write down partitions names in DisplayName and verify if one of them could be excluded from protection.

To exclude the partition from protection:

• Open Core console
• Click on agent name
• In the Summary tab, expand a list of protected partitions by clicking on triangle icon next to them
• Unselect all partitions and select the necessary partition
• Click on Set A Schedule, click on Advanced Mode, uncheck both weekdays and weekends, click Apply

Force a snapshot to verify that the issue is no longer happening.

Now if the partition must be backed up, then VolumeID should be changed. To do that, please access the protected machine and open CMD in Run As Admin mode.

• Assign a driver letter to the partition in question using this article: https://www.disk-partition.com/diskpart/assign-drive-letter-4125.html
• Modify VolumeID of the assigned drive letter so it'll be unique on the machine. https://docs.microsoft.com/en-us/sysinternals/downloads/volumeid
• Reboot the agent server
• Wait until agent status changes back to green (online)
• Using steps in the beginning of this article, verify that partitions IDs are no longer matching