It should be. One way to tell for sure is to block port 110 (nonSSL POP) at the firewall and see if everything still works - it should and it should route everything over the POP3S port (995).
My understanding was the "use secure authentication" was designed to secure (sic) nonSSL POP3 login credentials.
If you note, a number of sites that require secure communications do NOT require that to be checked, as there are bugs in it in various POP3 clients.
It should be. One way to tell for sure is to block port 110 (nonSSL POP) at the firewall and see if everything still works - it should and it should route everything over the POP3S port (995).
My understanding was the "use secure authentication" was designed to secure (sic) nonSSL POP3 login credentials.
If you note, a number of sites that require secure communications do NOT require that to be checked, as there are bugs in it in various POP3 clients.
refs:
http://sharkysoft.com/tutorials/linuxtips/pop3s/
http://www.nacs.uci.edu/email/secure-pop.html