Wie kann man einstellen, dass nur Admins oder der Ersteller des Themas posten dürfen?

[j.jaffeux (Joffrey Jaffeux)]

Generally speaking please have a look at https://meta.discourse.org/c/howto

I think you should be able to fix your issue with:

Understanding groups and category permissions (security settings)

See this video tutorial for an example of how to use these features: Create a private category with limited access for a certain group The Security tab on the category edit page is used to control both the visibility of categories and what users can do in a category. This is done by defining an access list of groups that associate a group name with an access level. The default permission for a new category is that the group everyone can Create/Reply/See. This means that a…