Mark is right.

The long read:
THE 2.0 IS NOT COMPATIBLE WITH FSX OR P3D2/3.
The 737 Captain (737-200, 737-100, 737-200ADV and 737-200C/F) version 2.0 for 64bit P3D4 is available.

How can I get the 2.X?

A. If you purchased P3D2/3 version before 20:00 UTC, 21 Jul '17:

1. Login to Your Profile.
2. Navigate: Product (737 Captain) > Extended Download Service then download the 737 Captain 2.0 to any folder on your computer.
3. Make sure the P3D4 is not running.
4. Double click the downloaded csy737_2XXX.exe file to install the 2.X.
5. Repeat steps 2 to 4 for the 737 Expansion models (if applicable) in any order.


B. All others including FSX version users:

You can buy the 2.X in our Online Store (full price, no discounts)