Sender Policy Framework (SPF) allows email services to verify the origin of a received message, and help counter forged and unsolicited email (spam). Email services receiving email from the Runbox domains may verify that the messages actually originate with the Runbox servers by looking up the SPF information in the DNS records of our domains.

The SPF policy for Runbox’ own domains states that mail should come from the server IP addresses we specify otherwise the mail will fail the SPF tests done by the receiving servers.

Note: SPF records only indicate to the receiving email service what the domain owner’s policy is for that domain, they are not a guarantee of how the receiving email service will use the SPF information (if at all) to determine what to do with a message.

Runbox Sender Policy Framework details

Please read the following section carefully as it may save you a lot of time and/or having to contact us.

If you use your own domain with a Runbox account, and send email using our outgoing SMTP servers, you can use the Runbox SPF record as part of your domain’s configuration. This will ensure that other email services can verify that mail from your domain originates from the Runbox servers and is less likely to be forged.

To do this you must include the Runbox servers in your list of approved senders. If you only send email through the Runbox servers the way to do this is to modify your DNS records to include the text below in a TXT record of your zone file.

"v=spf1 -all"

Note: In the Runbox interface do not include the quotes. Other interfaces may require it. You can usually tell by looking at any other TXT records your domain has.

The interface to your DNS management will most likely contain other fields that need to be completed, the values below should work fine in most interfaces (replacing with your own domain).

Please be aware that we are including a few examples here and looking at other records that already exist may help you determine which format you need to use.

Runbox DNS Management

TTL: 3600
Record Type: TXT
Value: v=spf1 -all

Some other DNS management interfaces may require something more like below.

Host: the @ symbol
TTL: 3600
Record Type: TXT
Value: "v=spf1 -all"

Note: The “dot” at the end of the domain name can be significant in some interfaces and without it the record may not work. You might be able to refer to other records that you know work to see how they are formatted.

Note: Some interfaces use the @ symbol instead of the domain as this is what is actually in zone file on the server. It can cause confusion because usually we associate @ with an email address. In this context it means the main domain you are adding a record for.

The SPF record above states that any server receiving email from your domain should check the SPF record at to see if the mail from your domain was sent from an allowed server.

There are other ways you can include the Runbox mail servers in an SPF record, but using the method above means you don’t have to worry if we change the IP addresses of our outgoing mail servers as we will update our record and your domain will include that record.

Sending mail via Runbox and other email services

If you need to send email from your domain through servers other than Runbox, or in addition to Runbox and wish to include an SPF record you will need to add further information to your SPF record.

To send only via another email service, please see the other service’s documentation for what the SPF record should be.

To send email via Runbox and another service, you might need something in the format below.

"v=spf1 -all"

In the case above represents what the other email service tells you the SPF record should be when using their mail servers. It may not always be as simple as the entry above, and we include this information here simply as a guide to the difference between using more than one mail service in an SPF record.

If you need help with this please contact Runbox Support.

More information about SPF