not a valid win32 application

[T.Slappy]

Is your script called hello_world.nsi and you want to include it in the installer?
It looks like recursion -> file hello_world.nsi is being read by NSIS compiler and also being packed into .resulting exe file.
Try to include some other file like "readme.txt" (create it)

[MSG]

Originally Posted by T.Slappy

Is your script called hello_world.nsi and you want to include it in the installer?
It looks like recursion.

There is no recursion. Including the script is a perfectly legal command.