There are duplicate entries about Backup Location in local Agent database that leads to retention rules failure
To resolve the issue, remove the Agent from Management Server and run a special script that will clear the local databases to avoid duplicates. After you re-add the machine to Management Server, Agent will obtain the necessary configuration data from it automatically.
Perform the following steps on the Agent that causes the error:
Delete the agent from Management Server: go to System Settings > Agents, select the agent and click Delete on the menu on the right
Acronis Backup Cloud: starting with version 7.8 update 2, the script is placed into Acronis folder along with Acronis Agent installation.
Acronis Backup 12.5: starting with Update 4 (Build 12730) the script is installed with the product and can be found at Program Files\Acronis\PyShell\site-tools\change_machine_id.py
If you are using an older build, download the script: click here.
If the problem reproduces after applying this solution, please collect a system report from the Agent where the issue occurs (see instructions for Acronis Backup 12.5 here and for Acronis Backup Cloud here) and contact Acronis Customer Central with a reference to this article.
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