How to activate a Virto product license on SharePoint Server
There are two methods of license activation: manual activation (offline) and online activation. You can choose either option depending on the availability of an internet connection at the time of activation.
The steps apply to SharePoint Server 2016, 2019 and Subscription Edition.
The License Manager is included in the .zip archive prepared for your component’s installation. Please unzip and install your component to begin the activation process.
To activate the license, navigate to Central Administration and find Virtosoftware Web License Manager. Click “Products”.

Here, you will see all installed Virto products.

On the right side of the screen, you can view the details of the person in charge; click “EDIT” to change them. If your server is connected to the internet, this person will be notified of any installed Virto product updates.
The first time you log in, the Contact information fields will be blank, and a window will pop up asking you to enter your details. Enter them and click “Save”.

Click the product name to open its registration page. The page shows the product version, the installed License Manager version, the servers of the farm with their roles, and the license status on the selected server, for example “Trial. 28 days left.”