I just tried to setup multiple inboxes as described in this Google video.
Unfortunately I notice that the "Save changes" ("Änderungen speichern") button is greyed out!
Maybe my filter-rule is wrong? I took a screenshot of the example setting that I tried:
I know that before I once had "multiple inboxes" in use, so I'm really confused as to why I suddenly cannot setup those anymore. As the tab shows up, the labs feature is obviously activated.
Best Answer
You cannot use "Priority Inbox" and "Multiple Inboxes" at the same time! You have to change from "Important first" to "Classic(al)" in either the little drop-down arrow on the right side of your "Inbox" or in the dropdown in the "Inbox" tab in "Settings".
Solution first found here and here on Google Groups.