Hello Chris,
Looking at the certificate it is valid till November of 2024 and has the shared mail hot name associated with it.
subject=/CN=newtekwebhosting.com
issuer=/C=GB/ST=Greater Manchester/L=Salford/O=Sectigo Limited/CN=Sectigo RSA Domain Validation Secure Server CA
Looking at the ports TLS1.2 is being offered.
If you use the shared mail server name (maila28.newtekwebhosting.com) for the IMAP and SMTP server do you see the same issue?
Thank you
~Tony
Tony Scholz
System/Network Administrator
SmarterTools Inc.
(877) 357-6278
www.smartertools.com