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Mail Tester
Email Port Checks


In order to receive email, ports must be open. There are a handful of ports (SMTP (25), MAIL SUBMISSION (587), IMAP (143), POP (110), POP SSL (995), IMAP SSL (993) and SMTP SSL (465)) each used for different purposes. SMTP and SMTP SSL and MAIL Submission are used to receive mail. POP, POP SSL, IMAP, IMAP SSL they are used by different mail clients to retrieve emails in your mailbox.

SSL Stands for Secure Socket Layer, even the NON SSL Ports should have an SSL Certificate installed in order to establish a TLS connection. Security has been rapidly changing and most mail servers don't keep their certificates up to date, leaving it vulnerable.  What most people don't realize is that even if you have a certificate that expires in 2 years, you can revoke and re-issue that certificate at zero cost. So updating a certificate to the latest version bears no monetary cost.

With Mail Tester we do extensive SSL Tests against all email ports of all the mx records we find. If we can't establish communication on an email port, we simply list that as a warning to bring it to your attention. You might not use POP and if you don't use it, their is no reason to have that port open and you can ignore the warning. If Mail Tester can connect to an email port and discovers no SSL Certificate is found, that will be flagged as a critical error. Mail Tester will then test the certificate for errors, cipher suites, protocols, key sizes and vulnerabilites and flag anything thats obosolte as a critical issue.

In additon, Mail Tester also does a SMTP Reverse Banner Check, to insure your server greeting matches the hostname of your mx record, if there is a mis-match, it can hamper your ability to receive mail from certain email providers.

Read out next blog in the Mail Tester Series: Mail Tester - SPF Records and Alignment

The Mail Tester Pro Report - Email Port and SSL Check Section

Email Port Checks for: mail.unlocktheinbox.com
Protocol Results
SMTP (Port 25): Connection Established
- Time To Connect: 1 Second - Passed
- Extensions: SIZE, 8BITMIME, PIPELINING, AUTH, STARTTLS, HELP
- Server Greeting: unlocktheinbox.com
- SSL Hostname: mail.unlocktheinbox.com
- SSL Subject: CN=mail.unlocktheinbox.com, OU=Domain Control Validated, O=mail.unlocktheinbox.com
- SSL Issuer: SERIALNUMBER=07969287, CN=Go Daddy Secure Certification Authority, OU=http://certificates.godaddy.com/repository, O="GoDaddy.com, Inc.", L=Scottsdale, S=Arizona, C=US
- SMTP Banner rDNS Check: Passed
- SSL Valid: Certificate is Valid
- SSL Protocol Used:: TLS 1.2
- SSL Cipher Algorithm: AES 256
- SSL Hash Algorithm: SHA 384
- SSL Exchange Algorithm: ECDH
- SSL Key Size: 2048
- SSLv3 Disabled: Yes
  
SMTP SSL (Port 465): Connection Established
- Time To Connect: 1 Second - Passed
- Extensions: SIZE, 8BITMIME, PIPELINING, AUTH, HELP
- Server Greeting: unlocktheinbox.com
- SSL Hostname: mail.unlocktheinbox.com
- SSL Subject: CN=mail.unlocktheinbox.com, OU=Domain Control Validated, O=mail.unlocktheinbox.com
- SSL Issuer: SERIALNUMBER=07969287, CN=Go Daddy Secure Certification Authority, OU=http://certificates.godaddy.com/repository, O="GoDaddy.com, Inc.", L=Scottsdale, S=Arizona, C=US
- SMTP Banner rDNS Check: Passed
- SSL Valid: Certificate is Valid
- SSL Protocol Used:: TLS 1.2
- SSL Cipher Algorithm: AES 256
- SSL Hash Algorithm: SHA 384
- SSL Exchange Algorithm: ECDH
- SSL Key Size: 2048
- SSLv3 Disabled: Yes
  
POP3 (Port 110): Connection Established
- Time To Connect: 1 Second - Passed
- Extensions: STLS, TOP, USER, LOGIN-DELAY, PIPELINING, UIDL, IMPLEMENTATION
- Server Greeting: unlocktheinbox.com
- SSL Hostname: mail.unlocktheinbox.com
- SSL Subject: CN=mail.unlocktheinbox.com, OU=Domain Control Validated, O=mail.unlocktheinbox.com
- SSL Issuer: SERIALNUMBER=07969287, CN=Go Daddy Secure Certification Authority, OU=http://certificates.godaddy.com/repository, O="GoDaddy.com, Inc.", L=Scottsdale, S=Arizona, C=US
- POP3 Banner rDNS Check: Passed
- SSL Valid: Certificate is Valid
- SSL Protocol Used:: TLS 1.2
- SSL Cipher Algorithm: AES 256
- SSL Hash Algorithm: SHA 384
- SSL Exchange Algorithm: ECDH
- SSL Key Size: 2048
- SSLv3 Disabled: Yes
  
MAIL SUBMISSION (Port 587): Connection Established
- Time To Connect: 1 Second - Passed
- Extensions: IMAP4rev1, UIDPLUS, CHILDREN, NAMESPACE, AUTH, AUTH, SORT, QUOTA, IDLE, AUTH, ACL, ACL2
- Server Greeting: unlocktheinbox.com
- SSL Hostname: mail.unlocktheinbox.com
- SSL Subject: CN=mail.unlocktheinbox.com, OU=Domain Control Validated, O=mail.unlocktheinbox.com
- SSL Issuer: SERIALNUMBER=07969287, CN=Go Daddy Secure Certification Authority, OU=http://certificates.godaddy.com/repository, O="GoDaddy.com, Inc.", L=Scottsdale, S=Arizona, C=US
- SMTP Banner rDNS Check: Passed
- SSL Valid: Certificate is Valid
- SSL Protocol Used:: TLS 1.2
- SSL Cipher Algorithm: AES 256
- SSL Hash Algorithm: SHA 384
- SSL Exchange Algorithm: ECDH
- SSL Key Size: 2048
- SSLv3 Disabled: Yes
  
POP3 SSL (Port 995): Connection Established
- Time To Connect: 1 Second - Passed
- Extensions: IMAP4rev1, UIDPLUS, CHILDREN, NAMESPACE, AUTH, AUTH, SORT, QUOTA, IDLE, ACL, ACL2, STARTTLS
- Server Greeting: unlocktheinbox.com
- SSL Hostname: mail.unlocktheinbox.com
- SSL Subject: CN=mail.unlocktheinbox.com, OU=Domain Control Validated, O=mail.unlocktheinbox.com
- SSL Issuer: SERIALNUMBER=07969287, CN=Go Daddy Secure Certification Authority, OU=http://certificates.godaddy.com/repository, O="GoDaddy.com, Inc.", L=Scottsdale, S=Arizona, C=US
- POP3 Banner rDNS Check: Passed
- SSL Valid: Certificate is Valid
- SSL Protocol Used:: TLS 1.2
- SSL Cipher Algorithm: AES 256
- SSL Hash Algorithm: SHA 384
- SSL Exchange Algorithm: ECDH
- SSL Key Size: 2048
- SSLv3 Disabled: Yes
  
IMAP (Port 143): Connection Established
- Time To Connect: 1 Second - Passed
- Extensions: FoundIMAP4rev1, UIDPLUS, CHILDREN, NAMESPACE, AUTH, AUTH, SORT, QUOTA, IDLE, ACL, ACL2, STARTTLS
- Server Greeting: unlocktheinbox.com
- SSL Hostname: mail.unlocktheinbox.com
- SSL Subject: CN=mail.unlocktheinbox.com, OU=Domain Control Validated, O=mail.unlocktheinbox.com
- SSL Issuer: SERIALNUMBER=07969287, CN=Go Daddy Secure Certification Authority, OU=http://certificates.godaddy.com/repository, O="GoDaddy.com, Inc.", L=Scottsdale, S=Arizona, C=US
- IMAP Banner rDNS Check: Passed
- SSL Valid: Certificate is Valid
- SSL Protocol Used:: TLS 1.2
- SSL Cipher Algorithm: AES 256
- SSL Hash Algorithm: SHA 384
- SSL Exchange Algorithm: ECDH
- SSL Key Size: 2048
- SSLv3 Disabled: Yes
  
IMAP SSL (Port 993): Connection Established
- Time To Connect: 1 Second - Passed
- Extensions: IMAP4rev1, UIDPLUS, CHILDREN, NAMESPACE, AUTH, AUTH, SORT, QUOTA, IDLE, AUTH, ACL, ACL2
- Server Greeting: unlocktheinbox.com
- SSL Hostname: mail.unlocktheinbox.com
- SSL Subject: CN=mail.unlocktheinbox.com, OU=Domain Control Validated, O=mail.unlocktheinbox.com
- SSL Issuer: SERIALNUMBER=07969287, CN=Go Daddy Secure Certification Authority, OU=http://certificates.godaddy.com/repository, O="GoDaddy.com, Inc.", L=Scottsdale, S=Arizona, C=US
- IMAP Banner rDNS Check: Passed
- SSL Valid: Certificate is Valid
- SSL Protocol Used:: TLS 1.2
- SSL Cipher Algorithm: AES 256
- SSL Hash Algorithm: SHA 384
- SSL Exchange Algorithm: ECDH
- SSL Key Size: 2048
- SSLv3 Disabled: Yes
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