No connection could be made because the target machine actively refused it

When you try to log in to the Veeam Management Pack for Microsoft System Center Web UI you receive the following error:

No connection could be made because the target machine actively refused it x.x.x.x:8084

Recommended Troubleshooting

• Ensure that Veeam Virtualization Extensions for System Center Service service is running.
• Verify that the domain account that you use to access the Veeam Management Pack for Microsoft System Center Web UI is a member of the local Veeam Virtualization Extensions Users group and a member of the local Administrators group.
• Verify that the local Administrators group has  Full Control access for the Veeam Virtualization Extensions UI website in IIS.
  • Open the IIS Manager.
  • In the Connections pane go to ServerName > Sites > Veeam Virtualization Extensions UI.
  • Right-click the Veeam Virtualization Extensions node and choose Edit Permissions from the menu.
  • Open the Security tab and check permissions for the local Administrators group.
  • Change permissions if necessary and propagate them to all child nodes.
• As a last resort, you can remove saved nworks data to reset any internal data sources that could contain saved credentials.
  • To do this, rename the vemState.db.xml file and restart Veeam Virtualization Extensions for System Center Service service.
    
    The vemState.db.xml file is located in the following directory:
    C:\ProgramData\Veeam\Veeam Virtualization Extensions for VMware
  • After that, you will need to add connections to VMware servers and configure monitoring settings in the Veeam Extensions UI once again.