How to reinstall vSphere Web Client plug-in for Veeam ...
https://www.veeam.com/kb184923.01.2014 · Solution To reinstall the plug-in: In Veeam Backup Enterprise Manager, go to the vCenter Servers section of the Configuration view. Select the vCenter server you need and click Check version. If a connection to vCenter server was a success, and the plug-in is installed in vSphere Web Client, the Remove link will become active.