Welcome to the forum.
For licensing issues, you need to contact Adobe Customer Support, and can likely do all of that via their Live Chat. This is NOT Technical Support.
If you are saying that you cannot get at Premiere Elements 10 to deactivate, then you need to contact Adobe via its Adobe Chat. That is one great group of people who can take care of the matter quickly and professionally in a few minutes.
I have found the following link to be the place to go. Once the link opens, click on "I still need help." to bring up the Adobe Chat pop up.
I have pre-set "2" for Serial number issues, or activating my product. Please double check to make sure that you find it set to that choice under the circumstances.
Please let us know if that works for you.
The Adobe Chat helped me to solve the problem.
Thank you very much for your help.
Have a good day.
2013/11/12 A.T. Romano <firstname.lastname@example.org>
Re: How to regain licence of premiere element 10?
created by A.T. Romano <http://forums.adobe.com/people/A.T.+Romano> in *Premiere
Elements* - View the full discussion<http://forums.adobe.com/message/5834221#5834221
Thanks for the follow up with the great news.
I am glad that Adobe Chat was able to help. That is a great group of people who work in that department, efficient and professional. Cannot praise them enough.