Such an annoying problem, especially for connecting to GMail via IMAP. I constantly get the error: Too many simultaneous connections. The worst part is this has been known ever since Leopard shipped: https://discussions.apple.com/thread/5820548 https://discussions.apple.com/thread/1207290 Any fix, Apple? UPDATE This problem seems to date much further back then Leopard. I’ve found references to this same issue in late 2003 (v10.3!!), here: https://hints.macworld.com/article.php?story=20031130150826388 Unfortunately, I don’t have access to server configuration as my problem is with GMail.