How is Veeam Backup & Replication licensed?
Veeam licensing for all products is described here: http://veeam.com/faq.html
You can verify your license key by logging in to www.Veeam.com with your credentials: http://www.veeam.com/manage_licenses.html. An updated key will be available for all customers with valid and active support contracts.
If you have difficulties retrieving your license file, go to cp.veeam.com, click "Open Case", and be sure to select "Licensing" to receive assistance from Veeam licensing.
To download Veeam products for trial license, go to http://www.veeam.com/downloads/. The trial license key is sent to you in email after registering. The trial license is valid for 30 days from the moment of registration.
To obtain a full license key for the desired number of sockets, refer to http://www.veeam.com/buy-end-user.html. The full license includes a one-year maintenance plan.
For example if your "Version" is listed as 9.x you are able to install any patch for Veeam Backup and Replication 9.0 or Veeam Backup and Replication 9.5