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BugZero found this defect 2528 days ago.
After migrating your Veeam Availability Console (VAC) installation to a new server, the following error message pops up when trying to add an existing Veeam Cloud Connect (VCC) server that was managed by the previous installation: Failed to install management agent on the Cloud Connect server
Adding the VCC server installs the VAC management agent on it which is required for communication between the two products. The error above means that the VAC service was unable to re-register the existing management agent.
1. Manually remove the existing VAC Communication Agent from the Control Panel snap-in on the VCC server: 2. Add the Cloud Connect server in VAC UI:
If you have any questions, contact Veeam Support.