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Optimum Online is committed to providing customers with an unparalleled Internet experience. As part of this commitment, Optimum Online has taken a strong anti-Spam position and has introduced the following Block list and E-Mail Acceptance policies to ensure customers continue to enjoy the best Internet experience available.

Optimum Online Block List Policy

Spam is an annoyance to customers, and if unchecked, degrades users' Internet experience. To reduce the amount of incoming junk e-mail or Spam and provide customers with the best Internet experience possible, Optimum Online has introduced third-party block lists to assist in filtering e-mail sent from known Spam sources.

These block lists contain the IP addresses of known spammers or insecure servers. When Optimum Online receives notice of abusive IP addresses from one of our third-party list providers, mail transfers from those IP addresses will be rejected until they are removed from the block lists. Individuals who attempt to transmit e-mail from a block-listed IP address will receive a "bounce" message that refers them to this page for information about the issue.

If you are unable to send e-mail to an Optimum Online customer as a result of your mail being blocked, you must cooperate with the third-party block list providers to be removed from the lists. Optimum Online neither operates nor controls these block lists and cannot have a restriction against mail from your IP address removed.  Please visit the web site of the third-party block lists mentioned below to verify your status and resolve the issue. You will be required to submit the IP address in question to these sites in order to verify your status. An IP address is a unique number assigned to each computer or mail server connected to the Internet.

Third Party Block lists used by Optimum Online:

Composite Block List - http://cbl.abuseat.org/
Spamhaus - http://www.spamhaus.org/sbl/

If you have been block listed and are not aware that your computer is sending Spam, your computer may have been infected with a virus, allowing malicious individuals to hijack your connection and deliver Spam through your connection. You may also be using an incorrectly configured proxy server or connection sharing software that not only allows the computers on your private network to share a connection, but the whole Internet as well. Be sure to consider these factors, as this may be the cause of your listing in a block list.

Optimum Online E-mail Acceptance Policy

Following are Optimum Online's technical requirements for accepting mail. The guidelines consist of industry-wide Mail standards, as well as other standards Optimum Online believes are necessary to provide customers with the best Mail performance possible. E-mail that does not conform to Optimum Online's Technical Guidelines will not be delivered. Optimum Online may block e-mail from any third-party at any time in order to protect our customers or infrastructure.

Technical Guidelines

All messages sent to the Optimum Online network MUST be RFC compliant. For more information about this, please click on http://www.rfc-editor.org.

Optimum Online will not accept:

  • E-mail transactions from IP addresses that appear on any of the block lists Optimum Online uses. Please refer to our block list policy above.
  • Connections from unsecured e-mail servers

Optimum Online reserves the right to verify that connecting e-mail servers are secure.

Any host that behaves as a mail transfer agent MUST accept bounce messages. Failure to accept bounces may lead to a block imposed on that host's IP address.