Windows Essential Mail 2012
(WEmail) is my choice, Thunderbird would be next.
WEMail takes some getting used to, there are tricks and tips
I use a few ISPs for eMail:
AOL, Gmail, and Outlook.com provide free POP2 and IMAP
- Yahoo charges 19.99 / year (other services included: disposable addresses.....)
You can test many eMail clients with the same server or different servers as long as you leave the msgs on the server and don't delete them when you delete the msgs in the client.
I strongly recommend that if you use WEmail that you manually configure all accounts when you're setting them up. Automatic configuration defaults to IMAP, not POP3.
Regardless of protocol, there seems to be other factors that might confuse WEMail if it's a non-standard configuration, even if you edit the account later and manually configure corrections.
sooo, manually configure new accounts in WEMail from the start based on the ISPs requirements