Hi
I found I can access to Members Only User Group without login.
Example
nation.marketo.com => Marketing Knowledge => User Groups => View User Groups => Japan Marketo User Group
It seems all internet user can access all Members Only Groups without access privilege.
Solved! Go to Solution.
Currently, JMUG was changed "Private" group type.
I understood Groupe type "Member Only" meens all people can read and can not post.