This should always be done from an Exchange management shell using the following command –
Move-ClusteredMailboxServer -id virtual server ID -MoveComment “Move virt-x to target node” -target target node
The command will run checks on the virtual server before attempting to move nodes. This phase may take up to 3 or 4 minutes. Use the cluster administrator to monitor the node move – this usually takes around 50 seconds to complete if all goes well!