Microsoft error 0x800CCC1A when sending/receiving emails

Outlook error '0x800CCC1A' occurs when

1. Mail server doesn't support legacy (outdated, insecure) connection encryption that your email client (Outlook) wants
   ( Recent SSL Encryption Bugs (like Heartbleed bug) require we discontinue outdated Encryption ciphers, protocols for your security. However your email client is not the latest stable, secure version and does-not support the latest secure Encryption ciphers, protocols! )
   
   
2. If in your email account Settings, wrong port number for the outgoing (SMTP) server is specified
   ( Ensure if using SSL/TLS on SMTP port is set to 465 or 587
   else set SMTP port to 25 or 26 )
3. If in your email account Settings, wrong port number for the incoming (POP, IMAP) server is specified
   ( Ensure if using SSL/TLS on IMAP port is set to 993 or if using POP3 port is set to 995
   else set IMAP port to 143 or POP port to 110 )
   

Resolution

1. Upgrade your Microsoft Outlook to latest stable, secure version or
   
2. Move to an alternate free Email Client like Thunderbird which supports the latest security protocols and
   
3. Recheck Email account settings ports
   

Else if all above cannot be done or fail then disable SSL/TLS Encryption in your email account Settings. Then try sending yourself a test e-mail message to make sure it works.