Mail App Launches Itself

[simon lefisch]

After updating to El Capitan 10.11.2, I started getting the annoying mail auto launches again! Argh!! So I was back to searching for a fix and trying this and that; then I stumbled on the following link. This helped me tremendously. Following the steps in this article cleaned up my mail library which was full of old email files. So far no more mail auto launches (knock on wood). It's a bit of work, but it's worth it. I hope this helps others.

Troubleshooting Apple Mail in OS X 10.11 El Capitan | Need Help 4 Mac

EDIT: Short term fix. Mail auto launched this morning.

Doesn't work since I've done a clean install of El Cap and only have a V3 folder.

 

[dmj102]

I filed this bug a few times using Apple Feedback since updating to El Capitan. Last month though, I filed a Bug Report and an Apple Engineer contacted me for more information. I ran a Terminal report for him. Then he came back and told me that my Bug Report was a duplicate and that was the end of it.

One of the strange things is that in my Mail Preferences>Accounts>Advanced>"Automatically detect and maintain account settings" is greyed out for my Gmail Accounts so I can't uncheck that. It's not greyed out for my iCloud account. I read that unchecking this setting could be a fix.

I tried a fix for the greyed out option by deleting my Gmail accounts in V3. Then in the Mail Data folder, I deleted the three files that have Envelope in the name, and in User Library>Containers I moved the com.apple.mail folder into the trash. After that, it's still greyed out and I still get auto launch. I've exhausted every avenue and given up now. I keep my MacBook Pro clean and always fix any bugs after upgrades, but this one truly baffles me.

 

[dmj102]

I already have my Hibernation Mode set at 0 to stop it from going into Hibernation overnight that I did with a Terminal command because there is no option in Energy under Sys Pref. I have been suspecting that Hibernation Mode is the culprit on my mid-2012 MBP because my Mail App randomly opens after 4 hours (overnight) and that's when Hibernation Mode kicks in, but lately this behaviour is occurring randomly during the day...arggh! I continue to check the web for a fix and yesterday I found this post:
mail app randomly opens | Communities

A poster in that thread provided a link on Power Nap:
How Power Nap works on your Mac - Apple Support

There is no SMC for Power Nap update for mid-2012 MBP (non-retina), but there is for MacBook Air mid 2012. There is no option to disable Power Nap in Sys Pref Energy on my MBP. It's only available on retinas.