The Solution Key is

• A set of four numbers assigned when the licenses are purchased for runtime deployment.
• An identifier of the organization that purchased the runtime licenses. 
• Set via the SetSolutionKey method. For example: 

PdfXpress1.SetSolutionName("ACMEImaging");
PdfXpress1.SetSolutionKey(0x1C3A023F, 0xA018F260, 0x37AF0E51, 0x557F2389);

The Solution Key must be set in order to use runtime licensing.

©2017. Accusoft Corporation. All Rights Reserved.