SPF is a record added to your DNS server, which helps verify that an email sender is authorized or not. In short, SPF "blocks" incoming emails from servers that you don't authorize thereby preventing fake emails from reaching your clients, posing as you. 

Creating SPF record for GFI MailEssentials

Here are the steps to set up SPF for GFI MailEssentials :

• Login to your DNS management console 
• Navigate to Tools & Settings > DNS Template
• You need to edit the DNS TXT record related to SPF
• An SPF TXT record for GFI MailEssentials will have the following syntax:  

mydomain.com  TXT  v=spf1 include:smtproutes.com include:smtpout.com -all

• Publish this record in your DNS records section for your respective domain.  

Note: If you don’t have an SPF record previously for your domain, simply publish the above-mentioned record to enable SPF for outgoing emails using GFI MailEssentials. If you do have an existing SPF record in your DNS, you need to modify it to include GFI MailEssentials, as shown below:

Previous SPF record:  v=spf1 include:spf.domain.com -all

Modified SPF record:  v=spf1 include:spf.domain.com include:smtproutes.com include:smtpout.com -all

• Save changes 
• Wait for 72 hours to allow your DNS to process the changes  

Finally, you can look up your record using our SPF record lookup tool, and enable DMARC for your domains: take a DMARC trial.