Thanks for your reply.
I saw in PDFCore.h, ActiveLicense will call other 3 methods depend on type, right?
In the code, it said:
case 1: activeProfessional
case 2: activePremium
default: activeStandard
On this case, what number should I use for type? That's why I use 3 for type.
However, if activation fails one time, can't I activate it anymore?
If I can re activate it, I already tried 1, 2, and 3, but watermark still appear.