Every once in a while there is a thread with 0 replies that has been marked as "Solved":
http://www.daniweb.com/software-development/cpp/threads/398278

When you sort by "Unanswered", I don't think these threads should be displayed (they currently are: http://www.daniweb.com/software-development/cpp/unanswered/list/8). Going through "unanswered" threads is surely in an attempt to answer some, and you most likely won't answer a solved thread.

David

Finding unanswered threads is an expensive process and it gets cached. Same with threads with zero replies. That's why sometimes some recently posted in/recently solved threads might show up in the list.