While most people never have an issue with their emails. One of the most basic ways to help prevent being black listed and prevent spam from being spoofed from your domain name is to set up SPF records.

Here is http://cldmv.net/ SPF record:

We’ll go over what each of the portions mean now.

v=spf1

This specifies what version the SPF is. Currently the only version supported is spf1.

mx

Specifies that email originating from MX records of the domain name may send email as well.

ptr

Allows any sub domain of the domain to send out email. This can be spoofed but not very easily. Generally someone would need to have access to your DNS records to change this. Also if you have an A Record with “*” pointing to your server this helps prevent this as well.

include:cldmv.net

Specifies that any domain ending in cldmv.net may send email for the domain as well. Generally this would be for your hosting provider to determine based upon their setup.

-all

Notice the negative sign. It tells servers which follow SPF to reject all emails which do not meet the previously set rules.

Anyone hosting email with CLDMV should set their MX record to mx.cldmv.net as well as add the following txt record in order to insure emails are sent and recieved following SPF.