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Sender Policy Framework (SPF) is an open standard aimed at preventing sender address forgery. We partner with SendGrid to provide us with reliable email delivery.
Custom SPF records
If you have an SPF record set for your domain already:
You must add a alphanumeric string before the all mechanism of this SPF record in order to authenticate mailings through SendGrid.
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In this example, we have an SPF record for the authorization of outbound mail for SendGrid. A -all inclusion versus an ~all inclusion indicates that this SPF record is the only record used to authenticate mail for your domain. Make sure to include any other authorized sender into this SPF record if you need to authenticate mailings from other sources.
Do not create more than one SPF1 record for a given domain. If more than one SPF1 record exists for a domain, you will want to merge any additional SPF records into one SPF record. You also cannot have more than 10 DNS lookups in your single SPF record.
Working with an existing SPF record
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If you already have an SPF record for your domain, you need to add SendGrid SPF inclusion into your existing record.
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