Sorry for bringing up a thread from 9 years ago, but: can we get descriptions of what all these flags do? Most are not described in the official NSIS documentation.

In particular, I'd like to know:

1. What is /NODESKTOP for? (If it's supposed to avoid placing an icon on the desktop, then the flag is bugged because that happens regardless.)
2. What is /NOUPDATE?

The flags I use are as follows: /PORTABLE /BACKUP /NODESKTOP /D=D:\mIRC