It is compatible:
https://serato.com/dj/hardware/controllers
What you need to do however:
Register at the serato.com website and add the license number you got from the Serato Upgrade package with your user name.
Start Serato.
Inside the Serato program there is an expansion button (lower right hand corner). Click it.
Log in with your serato.com account.
Click on “activate my product” and it will let you select a controller.
Obviously click on the Mixtrack Quad.
If you have purchased additional expansion packs (like F/X) click on “Activate all expansions” and it will activate anything you purchased.
Click OK and your done.
Everything should work nicely from that point on.
If it does not I would open a ticket with your serato.com account on the serato website.
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