Private categories (Login)

[KevC]

Let's get some terminology right first so everyone is on the same page.

Forums are inside categories.
So you have 3 categories and each of them have 2 forums.


EDIT: sorry I misread what you wanted.....

[dent11]

Let's get some terminology right first so everyone is on the same page.

Forums are inside categories.
So you have 3 categories and each of them have 2 forums.


EDIT: sorry I misread what you wanted.....

Correct! sorry for my english!

[warmweer]

I have been fighting for several days now. I can not.

I'm under the impression that it's not clear what you really want, partly because of the terminology you're using.

For one: categories are a special type of forum (sort of a container), with no topics/posts, but they contain forums (which may or may not contain subforums).
as such the statement I have 3 forums with 2 categories each. A:(1, 2)- B:(1, 2)- C:(1, 2) makes no sense.
In your example, I suspect you're referring to 3 categories (A, B and C), each containing 2 forums (1 and 2). Alternatively you could be referring to 3 forums with 2 subforums each.
example on phpbb.com

There is a category Support Forums containing 3 forums: [3.3.x] Support Forum, [3.2.x] Support Forum and Custom BBCode Development and Requests
You'll notice the the first 2 forums also have subforums.
Topics cannot be directly in the root of a category, they are in forums or subforums.

The other thing is "guests".
Per definition a guest is not logged in and has Guest permissions. As such anyone visiting the board without being logged in is a guest. Once logged in, that person is member of the group Registered Users (and possibly Newly Registered Users, if the board is set up that way and that user has not yet met the requirements to move out of that group).
Permissions are best set for groups, and only for special cases should you set user permissions (if you want one or a few users in a group to have extra or less permissions).
The aforementioned permission are not dependent on forums! They are board-wide. If you want groups (or user) to have a different permission set per forum then you need the Forum permissions.

I strongly suggest you have a look at the User Guide - Setting permissions and User Guide - Permissions and experiment with setting permissions on a private board.

Added: too slow in typing: KevC already pointed out the category/forum disambiguation. (leaving it as I typed it just for extra info).

[dent11]

Thanks.
Look this screenshot.

In this forum i was a visitor, this screenshot is before I register. When I registered I had free access to the text. Τhis is what i want to do

[warmweer]

Look this screenshot.

In this forum i was a visitor, this screenshot is before I register. When I registered I had free access to the text. Τhis is what i want to do

I had seen the screenshot but stevemaury already pointed you to a possible solution.
Nevertheless it's important to understand the permission system to set up the correct permissions for usergroups in specific forums.
Extensions can change behaviour or add behaviour but without understanding the behaviour before using an extension, you might end up creating a lot more work for yourself.