To uninstall the licence from your computer, you need to go in the software About... panel. To do so use the menu: Help->About...
Press simultaneously the Maj+Ctrl controls of you keyboard. The Ok button will then turn into Licence, click the Licence button. You will need to wait a few seconds before that the activation panel appears.
In the activation panel, tick the box: Remove licence.
In the Activation code field, which is now available, write your activation code. If you forgot it, keep in mind that you can find it in your OBDuCAN bill as well as in your aquisition e-mail.
Click now the Continue>> button, this operation will need your confirmation. Indeed, when a licence is deleted from a computer it is not possible to install it again without changing the activation code. In other words, the former activation code will turn invalid.
The following window will indicate you that the removing operation went well. You now have your Removal Code wich will allow you to prove that you successfully removed the licence from your computer.
Caution: before clicking the OK button, make sure to copy/paste the removal code because it will be asked as a removal proof!