An agent is already available on the target host, and it may be in use by another backup server. This situation typically arises when the target host has a BDRShield Delegation Service installed by a different BDRShield Backup Server or BDRShield Client.

To resolve the issue, follow these steps:

1. Check for Existing BDRShield Delegation Service:

1. Open Control Panel and navigate to "VembuIntegrationService."
2. Use Services.msc to check for the presence of "BDRShield Delegation Service."
3. Confirm whether the BDRShield Delegation Service is already installed on the target machine.

2. Decision Process:

1. If the BDRShield Delegation Service is already present and you intend to continue using it with a different BDRShield Backup Server or BDRShield Client, proceed accordingly.
2. If not, remove the existing BDRShield Delegation Service from the BDRShield Backup Server or Client where it was originally pushed.

3. Removal and Addition Process:

If you decide to remove the existing BDRShield Delegation Service:

1. Uninstall the BDRShield Delegation Service (VembuIntegrationService) manually from the control panel. (Refer KB: https://support.bdrsuite.com/portal/en/kb/articles/uninstalling-bdrsuite-delegation-service-bds)
   
2. Proceed to add the BDRShield Delegation Service from the desired BDRShield Backup Server or BDRShield Client as a fresh installation.