how to?

if not to use .NET what to use?

Depends, Managed or Unmanaged?
IF Unmanaged you can use QT, or Wx DEV's GUI programming capabilities..
If managed, well your only option is kind of .NET

.NET is not that bad. Stop saying things based on your bad opinion.

Give me reasons people should use it and i might consider stopping posting about it.

Faster Development

A horrible reason.
You can develop just as fast in unmanaged C++.

A horrible reason you say.. Of course that you do a lot of development daily to experience that... o.o
But since we are on a mood for reasons, tell me reason why .NET is bad, a valid and decent one please. (that is not horrible, and it is actually on the windows forms theme, not hacking or what so ever)

-Less probability to have errors equals faster development.
-Faster compilation time (unless you do some machine distribution). And you would know this if you ever touched on a project with a few thousand lines, so equals faster development. (5mins to few secs compilation)
-Less code to write as .NET already have lots of libraries supporting your daily needs.
Etc... this are the ones that just came out of my head.

We shouldn't act like code monkeys nowadays if someone is already providing us something to help with development.
You are just an hater and want to look cool by being part to the C++ Leetzorz only. wtf

Windows API, or the C++ equivalent, MFC.

Qt requires purchase if you want to distribute your applications, and you still can only use the free version (i think)

WxWidgets is Free, but from experience, i do not like it

I stay with C++ and only C++ because i cannot be bothered to learn another language xD

I tried learning C# but i couldn't pay attention for more than 15 mins at a time. Same with Java and Perl....

Bai bai, last day of school !!

Honestly, I don't like .NET (not saying that it's bad, just saying my opinion). I don't like it because, I am a real control freak, and i want to control everything. I can't stand it when I have to only write a line of code that does many other procedures that i don't know about. It makes me feel stupid. That is why i have a big hunger for coding GUI applications from scratch. It may look worse than if i did a GUI with .NET, but I don't get that feeling of accomplishment.

I know it sounds really weird, but it's true, that's how i feel (if anyone cared to know, lol).