Eroor Upgrade from parallels desktop 8 to 11

Hello,
I have buy, download and install the upgrade to parallels desktop 11.
Unfortunately, I have done that on a version 8 of parallels desktop.
The registration key doesn't work. I have read on the support web site that upgrade need at least version 9.
Now each time a start parallels desktop, he ask me the registration key and I have no access to my windows virtual machine.
I would like to cancel the installation and go back to version 8, in order to backup all data in my windows virtual machine. After that I will buy the full version of desktop 11 and reinstall it.

Is it possible? How can I do that?
Thanks for your help.

Brancart L.

 

Hello Brancart,
Please check your private message and reply us.

 

Hello. I have nearly the same problem. I haven't seen that it's impossible to upgrade vom Version 8 up to 11 so I bought just an upgrade and now I can't use it. Is it possible to make an additional payment to get the full version?