There are three technical steps on the server side that one can take to keep one's domain off of an ISP's spam list.
First of all, if you host with ebwebwork.com, then our staff will make sure to create a Sender Policy Framework (SPF) record and an rDNS record, and implement the DomainKeys authentication protocol, for your domain. This ensures delivery of all of your email.
What is Reverse Domain Name System (rDNS)?
The Domain Name System (DNS) is the system that relates an Internet Protocol (IP) address to a recognizable domain name like ebwebwork.com. Reverse DNS is DNS in reverse: rDNS relates a domain name to a valid IP address. Reverse DNS is a useful antispam method because it confirms that a domain name is associated with its correct IP address.
When I set up your email accounts I make sure to implement for your domain a valid rDNS record. This helps to keep your domain off spam blacklists. An improperly configured rDNS record will signal spam watchdogs, like Spam and Open Relay Blocking System, that your email server's IP address is questionable.
What is SPF?
SPF is a security measure that detects email spoofing. Wikipedia has a useful article on SPF:
http://en.wikipedia.org/wiki/Sender_Policy_Framework
What is DKIM?
DomainKeys Identified Mail (DKIM) is an email authentication protocol.
The function of DKIM is to authenticate every valid email message that is sent from your domain. Valid messages are assigned an encrypted security code. A matching security code is placed in the domain's DNS (domain name system) record. Messages that contain the correct security code are valid. Messages that do not contain the correct security code are not valid and are probably spam.
You said you set up DKIM for my email account. What if I want to test DKIM?
Glad you asked. It is a good idea to make sure that your DomainKeys authentication is valid. Take these steps:
More resources regarding DomainKeys, DKIM, and email anti-spam methods:

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