My Addictive Drums II just stopped working because it says I'm not on the same CPU that I installed it on... which is odd, because this is the only computer I've ever installed it on... 
Suggestions?
(Platinum, long past the 12 months, still paying my upgrade fees)

Have you done a Window 10 Upgrade, or had a Update run?

I cannot tell if you are running Win10 but it is a known issue when upgrading to Win10 and the Win10 Anniversary update. Use the XLN installer to get AD2 to recognize the PC again.

Also what happens when you run the XLN Installer. It might do repair

I don't think I've had this exact problem (different CPU) but I do know AD2 recently become unauthorised on my pc. I just authorised it again (you may have to kill a previous authorisation). I just worked through the different parts of AD2 and Bob became my uncle.

Grum.

Hi - I would think that is some sort of AD2 issue - perhaps you can log on to their site and look things over with your account there?  Sometimes hardware changes can be seen as changing to a different computer, as differing combinations of things like CPU serial and motherboard serial get computed into some sort of encrypted ID for what it determines to be a particular computer.  Have you done any hardware changes for this computer?
 
Also, you have the following at the end of your post:
 
"Platinum, long past the 12 months, still paying my upgrade fees"
 
And I thought I would ask you to expand on that, so I can make sure I understand what you meant - are you wondering why you are continuing to pay monthly charges?  IF that is so, to the best of my knowledge the monthly update option continues until you decide to either change your options, like to a one-time yearly fee or the lifetime updates, or cancel the monthly updates.  IF you were to cancel monthly updates, Sonar would continue to run forever, but would not receive any additional updates or features from the date of cancellation forward.
 
Bob Bone

Robert, that's just so I can show that I'm ruling out that my subscription expired.  I know the continued fees are for upgrades, though the one of the emails sent by Cleverbridge always makes it sound like they'll shut down your Cakewalk completely if you don't pay up.  (Last month, they sent me an email on the 18th saying it "was due" on the 25th (a week later) and that if I didn't pay by the 20th, they would deactivate my Cakewalk.  I'm sure they meant to phrase the whole email differently).  
 
Reinstalling ADII to see if that works.

GO to your XLN account on line and remove the computer from your account and then reestablish the computer connection again and it will work. 
 
Here, Read my post about how I fixed my problem. 
http://forum.cakewalk.com/Addictive-Drums-2-Reverted-to-Demo-Mode-Solved-m3412421.aspx
 
 

That did the trick.  This is the first time I'd loaded Addictive Drums since the Windows Anniversary update.  Apparantly, this is a major upgrade, and changes the identifying information.  
 
Thanks for the help, guys.

Tkrain,
 
Glad things worked out for you.