Yes, it is possible to delete sessions.
The 'License Monitoring Details' page displays information on the license allocation. You can see the following:
If you want to delete a user from a remote machine, you have to change the access mode in the WebAdmin on the server machine.
1. Open the WebAdmin.
2. Open the Configuration tab and choose the Basic and WebAdmin options.
3. Click the radio button for Require Authentication.
4. Set a user and a password.
5. Click Apply to save the settings.
Every instance of ARD registers as a license usage as it requires a license to open ARD. However, with version 2.6 we have a new feature in place which opens accessed flows within the same instance (double clicking or drag and drop on to canvas). It just opens as a new tab instead of consuming another license.
Usually after deleting the user session or restarting the server, all handles will be released. If the Client machines are still connected to the Server, the will reopen this handle again. If ARD is running on the client machine and you release the handle from the server, the application tries to reopen this handle for the next usage; usually next Runtime Check. This means if you remove the client and the client is still running, the application will allocate a license again. Deleting the license via Web Admin is suitable for clients which are still holding the license, but are not online anymore. However, if the user still has ARD open, then the server will allocate an additional license.
Since the license is external to ARD, their only job is make sure that the applications are running smoothly with a license. It is not a session like a Web Application. Due to the the runtime check, there is constant polling of the licenses with a time interval, and this is so that the user is able to use the license and ARD. We do have a runtime check since we use AxProtector to encrypt the application. We can only exit the application to release licenses. The only way to make sure the application is running smoothly is with polling and runtime check. If there is no running instance of ARD then the license is returned back.
This document outlines how to remove and block users from the license server: https://support.ca.com/us/knowledge-base-articles.TEC1749392.html.