When I try to reinstall Movie Edit Pro 2016 its asking me to reregister then deactivate program don't understand
Welcome to the Magix user to user forums.
There is a limit on the number of activations allowed for all, fairly recent, Magix software. I suspect MEP 2016 is one such app.
As a user you have an activation limit of 2; it would seem that you have previously had the program installed and later reinstalled. Hence the problem you now have since the Magix server believes you are attempting to activate the software for a third time, at least!
What you need to do to rectify this: Go to your Magix account, log in and go to My products. Find the listing for MEP 2016 and you should see the serial key (it's worth checking that you have entered it correctly) and then under "Show more details" you will find a list of all activations currently on your account. Select the option to deactivate any and all that are no longer in use.
Then, in MEP 2016, try again to register and activate.
If you do not know your password for your Magix account you can click on "I have forgotten my password" on the login screen and then you will need to wait for instructions on how to carry out a password reset.
HTH
Jeff
Forum Moderator