For several days now, marking all messages read does not remove unread star (Windows 11.)  Each time I come back into Delphi, all messages show unread.  

Try logging out, then log in at https://forums.delphiforums.com/myforums and use the links on that page to go to your forums. 

Make sure any links or bookmarks you use have https, not just http.

let us know how it goes  ...

Seems to have worked.  Thanks!