Can anyone tell me what this means and how to fix?

[Bigbbubba]

I've used aqua mail for the past 3 years at least I'd say and it pops up with this earlier today and it won't bring in new mail. I can log into the mail online and it comes up and I've even tried other email apps and they worked.

[Kostya Vasilyev]

Your server's SSL certificate has changed and is now self-signed.

Please change "Security type" from "SSL strict" to "SSL accept any" on the incoming server settings screen (bring up account setup screens which is in your screenshot - tap Manual not Next to see detailed incoming server settings).