Faulty PC and lost license...

I have purchased licenses for 3 users/PC’s. One of the PC was broken - fell and died :(. How can I transfer the license from the computer to the new one? After opening the page http://licensing.emclient.com/ appears login window. What information do I enter there?

Use this Free tool for locate and find your lost eM Client activation key - http://www.birdiesoftware.com/em-client-key-locator.html

Unfortunately, it does not solve my problem, because I have the activation key. The problem is that the new PC, there is information that I used all the license. And I can not start a new installation eMclient, because I can not deactivate this on the broken computer. I tried to login to License manager, but no results.