I have a number of local folders and set up rules to send certain emails to certain folders. In one folder (and only one), emails show up when unread. However, after reading an email and switching to another folder, when I go back to that folder no emails appear, even if I did not delete the "read" email and even though the folder shows that I have over 70 emails in that folder. All my other local folders work correctly.

Is there some setting I inadvertently set that could be causing this problem? I already tried "Repair Folder" and nothing changed.