I have an Apple iPhone 6, version 9.3.1 which has stopped being able to access my mail suddenly last week. I get a box saying "logins are disabled for 'IMAP account'"
iMac (21.5-inch Mid 2011), OS X El Capitan (10.11), mail won't send out
Check with your email provider
Some email providers charge a fee for IMAP usage
I have had this account for many years. And my mail is working on my iPad and iMac. It is also not working on my husband's older Mac Pro.
Then try to delete the email account
Do a forced restart - After shutting down all open apps using the app switcher - invoked by quick double press of the home button and swiping up on each app till it flies off the screen.
Hold the sleep/wake and home buttons down together till you see logo - then release and allow normal boot up
Re add the account back in
my mail stopped working on my phone and shows a box saying "logins disabled for IMAP account"
