My Outlook 2013 has recently acquired a nasty habit that's driving me nuts.

I have several accounts, and in the mail window I have the various inboxes shown in the navgation pane. My central pane is the mailbox contents, and the preview window is over on the right. I do not have preview turned on for the mailbox contents list. At the top of the mailbox contents is the single "Search all mail items" box.

Now I'm familiar with how this works - or worked, at any rate. Click on the box, get the detailed search window up. Do your searching. Click the handy large red X on the search toolbar ribbon, back to the inbox.

Not any more. Now it sometimes closes. Sometimes it says "nothing to show here" until I click the inbox folder again. Clicking the inbox folder seems to toggle between about three states - message list, search box, and the "nothing to show here" message in a pseudo-random fashion. Clicking a different inbox and then going back to the first inbox results in a random state.

It's driving me nuts! Any ideas?