I can’t find any way to block ALL traffic of a programm (Firewall).
How can I do that?
You can’t find it because it would it isn’t making any sense at all.
Blocking all outgoing connections also mean you can visit any website, can’t end/receive mail etc.
There is only one way to do it, disconnect from physically to any network.
Uhm, sorry, but it well makes sense.
Edit: Even Windows Firewall can do that, m8.
Examples:
I’ve got software that I don’t want to use my bandwidth.
Software I don’t want to call home.
Software I only want to use locally.
Software I don’t trust.
No, you it doesn’t make sense to want to disable ALL outgoing traffic as you asked.
If you don’t trust software you should not have it installed.
Some software needs to “call home” to check for updates/(security) patches (e.g. avast)
If you want to use software only locally, use it a VM without network options.
No.
It IS possible, I just found it.
We’ve got to klick on that small bar on the very left (see screenshot).
http://i.imgur.com/q6bHdFe.jpg
But thanks for your “opinion”, Evangelist.
Simply hit the button to kill the WiFi. That will stop all communication in and outbound.
Maybe I wasn’t clear enough but my intention was to block a specific programm.
Nevermind I found out how it works now. 
The translation of that button is quote: “ask for all connections”, so it’s a bit confusing because now your saying:
However before you had posted quote:
Which sounds like you want to shutdown ALL TRAFFIC and NOT just “block a specific programm” as you now say.
It’s good that you’ve solved the problem but I’m just a bit curious, so how does selecting “ask for all connections” do what you now say you intended which is to block one “specific program”? ???
Guys,
Maybe the OP was not clear about what he wanted.
And maybe he was not clear about that he is using the Avast! firewall.
But we are here to help people, NOT to blame them for their mistakes !
But the OP found the right solution.
A guide how to configure the Avast! firewall https://www.avast.com/en-us/faq.php?article=AVKB25#artTitle
Greetz, Red.
WinPrivacy can block any program from accessing the internet.
Yeah, but I don’t see any use for it if you are already using a software firewall.
And all other funcionality can be covered with free tools as well.
Greetz, Red.
It’s a good think we are all entitled to our own opinions.
Of cource it’s a good suggestion
But why should the OP buy a new tool for something he can acomplish with the software he already has ?
That is using the Avast! Firewall for blocking any program to access the internet.
I thought maybe Gopher John missed that.
Greetz, Red.
The OP asked:
How to block outgoing connections completely using firewall?
The answer to that is really simple.
You can’t without loosing all network/internet functionality.
Looking at the picture he provided, it seems his natural language is German.
Perhaps it is better for the OP to ask next time in the German section to avoid (translation) problems.
Just in case: https://forum.avast.com/index.php?board=24.0 