I've been using K-9 for many a year on various Motorola Droid phones and never experienced this problem. About two weeks ago I got a Samsung Galaxy S8 and I'm seeing the same as the others here. The S8 is running Android v7 and I'm using K-9 Mail v5.207. And yes, my settings are correct. I have five email accounts in K-9 - three are push and two are pull. But the only way I can receive mail is to do a manual sync. I did have it working for a couple of hours one day by deleting the two pull accounts and then restoring them. Polling was taking place every five minutes, but after a few hours, the dreaded "syncing is disabled' message showed up.
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