Sender ID_SPF

Sender ID/SPF prevents other people/servers from pretending to be you. Sender Policy Framework (SPF) is similar to DomainKeys/DKIM since it validates you as the sender; however, the implementation is different from DomainKeys/DKIM. SPF works by publishing what is called a "reverse MX" record to tell the internet what machines are allowed to send mail from the domain.
Sender ID and SPF are different. Both validate email sender addresses using similar methods, publish records in DNS and use the same syntax for their policy records. They are different in what they validate and the layer of the email system they check.
Sender ID and SPF is configured outside of Lead Liaison and should be done by your company. The setup requires changing your DNS record. You can check where your DNS is hosted here: http://whois.domaintools.com/ and possibly enlist support from your DNS host to help you change the record.
There are wizard's to help configure SPF and Sender ID available here:

• SPF: http://www.openspf.org/
• Sender ID: http://www.microsoft.com/mscorp/safety/content/technologies/senderid/wizard/

Here are a few simple rules to keep in mind when configuring your Sender ID / SPF record to work with Lead Liaison:

• If you already have your own SPF or Sender ID record set up, all you need to do is add "include: leadliaisonconnector.com" to the existing record and you're done.
• SPF clients ignore records which do not carry a recognized version such as "v=spf1".
• A domain MUST NOT return multiple records that begin with the version "v=spf1". If more than one "v=spf1" record is returned, this constitutes a syntax error and the result is "unknown".