Mar 30, 2019 See also: Mail App Keeps Crashing. 2- Set up your email account using IMAP. Please note that this process will delete your messages and will no longer available on your Mac. But do not worry, your mails will not be removed from Google’s servers, you can still access your mails via gmail.com web site. Here is how: Open the Mail App; Click Mail.
- My Apps: Add apps to your account, edit app information, create new versions, and submit your app for review.Also, configure App Store technologies such as Game Center, in-app purchase, and TestFlight. App Analytics: View analytics that track user app acquisition, usage, and monetization. For more information, see About app analytics.
- Create an Apple ID if you don’t have one. Log into iCloud in the iCloud system preferences. Enable the “Back to My Mac” service.
Denis Gomes Franco
Well-Known Member
Mail Enabled Service Account
- Sep 3, 2018
- 45
- 7
- 8
- Tupã, São Paulo, Brazil
- cPanel Access Level
- Root Administrator

I double checked every setting on this application (via TeamViewer) including TLS/SSL and IMAP/SMTP ports, to no avail. Also tried connecting non securely. It simply says it cannot verify the username and password. And the weird thing is: the Outlook app on mobile can connect just fine.
But here's a thing that might shed a light on this: Outlook 2016 on Windows was able to connect effortlessly, but only after throwing an INVALID CERTIFICATE error. That certificate says it was issued to 'serverhost.serverdomain.com' (my hostname and domain of course) while I'm connecting to 'mail.customerdomain.com', so obviously there is a mismatch - even though Cpanel correctly issued and installed an SSL certificate to 'mail.customerdomain.com'.
So, how do I resolve this?
Several Mac users have reported an issue in which email accounts (Yahoo or Gmail etc) cannot be added. Users receive the following error message:
Connection Insecure
Failed to verify the server certificate. This could be because of your network configuration or your proxy settings.
You may also see experience this problem when you want to send or receive mails, because Mail app on your Mac may not connect to your email account.
Even though this error message says this could be because of network or proxy setting issues, users have stated that they are experiencing this problem when in fact there’s no network connection or proxy issues.
Fix Connection Insecure Problem
If you are having this issue, here is how you can troubleshoot:
1-Try temporarily disabling your antivirus software. It is known that sometimes antivirus software may cause this problem. If this solutions does not solve your issue, read on.
2-Expired / revoked SSL certificates may cause this problem. Find and remove them. Here is how you can fix it:
Mac Mail App Connection Logging Enabled Mail Mac 10 14
a-Launch Keychain Access (Applications > Utilities).
Disable Connection Logging Apple Mail
b-Select “My Certificates”.
Mac Mail App Connection Logging Enabled Mail Mac 10 13 6
c-Now, find expired / revoked certificates, if any. Expired / revoked certificates will have a red X sign. Find also certificates with a red X mark saying “This certificate was signed by an untrusted issuer” or “This certificate was signed by an unknown authority”. When you find them, delete them.
Mail Enabled User Exchange Online
d-When you are done, restart the Mail app.