Can you add the option to run a command that will logoff the windows user when you disconnect the session? Otherwise it just leaves your connection for the session listed as "disconnected" and uses up a licence.

Unfortunately, that's not possible.

You can, however, use Group Policy to make some adjustments that might work for you. One option you can set is to log off on disconnect, so that when you disconnect, the user is logged off automatically. Additionally, you can set a timeout for disconnected sessions, so that after so many hours, it will automatically log off.

What about adding an option to RD Tabs to run a command when you select disconnect - such as "shutdown -l"?

The problem is that there is no way for RD Tabs to interface directly with the remote session. What you suggest would require RD Tabs being able to send a command to the remote session, which isn't possible (at least easily). The only way I can think of it working would be to use sendkey function to spit out a keyboard macro while the remote session is in focus. The problems with this is that if you click away you'll see a bunch of keystrokes spit out to some random location (possibly your local computer) which wouldn't be too much fun with RD Tabs logging you off your local computer. 😉 Additionally, there is no guarantee that input focus will be retained correctly, even if you didn't touch anything while it is happening. For instance, if an app pops something up on the remote session while the keystrokes are playing, it could potentially activate something or dismiss something you didn't mean to because of shortcut keys. I don't feel comfortable doing it.

That said, in the next version of RD Tabs you will be able to execute PowerShell code at events. One of the events will be disconnection. There would be nothing stopping you from implementing the above solution where you can spit keystrokes out using sendkeys on disconnection, and hoping that the macro (WIN+R, shutdown -l) works. 🙂