SQL Server 2014 change license key I need to change the Microsoft SQL Server 2014 license key (just key - not versions). I have found that it is possible via SQL Server Installation Wizard:  


http://www.alexandreviot.net/2015/11/10/sql-server-2014-how-to-change-the-product-key/  
http://www.sqlcoffee.com/SQLServer2012_0015.htm


Do I need to stop SQL services for that? Or will some downtime be needed? 
I think that when upgrade is clicked, SQL services will be restarted probably, right?
I have been going through this exercise for a large amount of servers. I am not going to explain why I am doing this due privacy reason.

I will give you high level steps and let me know if this is not enough.


Get binaries for the version you want to change to.
Start setup.ext
Chose maintenance-->Edition upgrade
Follow standard installation process
If you have more than one instnace on a single host choose the
intance you want to change key.
For me it normally takes about 5 minutes.
Will not ask for a recycle of SQL Server engine in most cases.Microsoft engineers recommend you do a recycle anyway.  You can stage the change before you schedule maintenance window to avoid an extra downtime.