The issues started occurring after upgrade to 10.11 but not sure if related or not.
I have 2 gmail accounts defined on my Mail app. Most of the time (around 70% or so) all is healthy.
But every few minutes, the alert signs show up next to both of the accounts. The connection doctor points the blame at IMAP
This lasts for a while, usually a few minutes. I immediately check my internet connection by pinging various public IPs - all is rock solid. After a while this goes away.
Any idea why this may happen and how I can troubleshoot? I'm tending to not suspect an account setup issue as all works well most of the time. BTW - both of the accounts were set up very basic - just selected Gmail as the account type and added user and password. Did not mock around with anything else more advanced.