I would like all topics to have category.
So if I choose allow uncategorized topics then general will disapear but also I can’t create category named General.
How to make General category to all uncategorized topics?
AI-generated summary
The discussion revolves around making the ‘General’ category the default for uncategorized topics in a forum. zbor initially wanted to rename ‘Uncategorized’ to ‘General’ and have it appear by default. cpradio suggested renaming ‘Uncategorized’ back to ‘General’ and disabling it, then creating a new ‘General’ category. zbor confirmed this worked but asked how to set ‘General’ as the default category for new topics. cpradio explained that without ‘Uncategorized’, a category must be selected, but zbor noted ‘General’ wasn’t appearing on the homepage. cpradio identified the issue as the ‘suppress uncategorized badge’ setting being enabled, which hides the badge. zbor confirmed the issue was resolved by disabling this setting.
I have a feeling you at one point renamed Uncategorized to General. I’d recommend renaming it back and then disabling it.
Then create a new category, with access for Everyone, named General
That did the trick.
How now I set that creating new topic has that General category by default instead a selecting category?
So when opening new topic it goes to General, unless it’s changed?
I don’t think there is a way to do that. The only way to do that was to leave Uncategorized enabled and rename it to General (like you had before). But when you get rid of Uncategorized altogether, you must select a category when creating a topic.
But in that case General doesn’t show in category listings.
It does for me… Or at least on the staging site for Sitepoint it does. When I visit the Categories area, I see Uncategorized. Also shows there when I rename it to “General” too.
Is Categories your homepage? Did you accidentally check “Suppress this category from Homepage” on the Uncategorized Category Settings screen (when you choose Edit Category)
Ah, check this site setting
suppress uncategorized badge which states: Don’t show the badge for uncategorized topics in topic lists.
Make sure that is unchecked
You are life saver 
Solved.