Native C# Protection (NCSP) is a protection tool for C# 2003 applications.

The goal of NCSP is to produce trial versions with limited functionality of C# applications. With the correct NCSP Key these applications work as registered versions.

NCSP advantages:
(1) protection of not code, but data needed to run the application;
(2) use of only native (but peculiar) to C# means;
(3) the protected executable is natively compiled by C# (no compatibility problems therefore);
(4) no external processing of C#-produced executable;
(5) the Key is not checked but is used to restore the protected functionality;
(6) each Key contains personal data, therefore each one may be easily identified.

NCSP protects not code, but data needed to run the application. In case of C# applications data is a correspondence between events and event handlers.
The difference between trial and registered versions produced by NCSP is based on use of different event handlers for trial and registered versions of the protected application.
NCSP protects forms of C# project on the source level, i.e. NCSP temporarily modifies the source code, then, after re-compiling, the application is protected.
The protected application does not use a call of some checking routine to choose which set of event handlers to use. Instead it uses data containing in NCSP Resource and in NCSP Key to assign registered event handlers to the corresponding events. If the registered event handlers cannot be assigned (there is no or wrong NCSP Resource or NCSP Key), the application uses the trial ones.

More information about NCSP may be found at http://www.posolsoft.com/NCSP