Error on every email even tho they send

How do I get rid of this

What are your email accounts server settings for Incoming and Outgoing ? Also are you using an IMAP, Exchange or POP Account ? Lastly are you using EM Client for Windows or Mac.

My email setting are: IMAP - 143 and Force usage SSL/TLS and SMTP - 587 and Force usage SSL/TLS

I am using IMAP and not POP and on a Windows computer.

I have not changed any of my settings prior to this starting.

Ok. Are you running any (optional / third party) firewall or security / antivirus programs ?

If you are, try disabling any of those programs temporarily to see if any of those are the cause as that error has also been know to be sometimes caused by optional programs installed.