A customer tells you your quote never arrived. It did, straight into their spam folder. Here is how to find out why, in order of likelihood.
1. Authentication records
Receiving servers check three DNS records on your domain:
- SPF lists the servers allowed to send for your domain.
- DKIM signs each message so the receiver can verify it was not altered.
- DMARC tells receivers what to do when SPF or DKIM fail, and sends you reports.
Missing or broken records are the most common cause of spam filtering today. Check them with our DNS checker, and make sure you have only one SPF record.
2. Sending from the right place
If you send through a website form, a CRM or a newsletter tool, that service must be included in your SPF record and should sign with DKIM for your domain. Otherwise its messages fail authentication.
3. Reputation
Servers remember how recipients react to your mail. Sending to old, purchased or unverified lists produces bounces and complaints, which damage the reputation of your domain and server. Clean your lists and never buy addresses.
4. Content
- Avoid subject lines in capitals and excessive exclamation marks.
- Do not send a single large image with no text.
- Make sure links point to your own domain, not to shortened URLs.
- Include a clear signature and, for marketing email, an unsubscribe link.
5. Volume
Sudden spikes in volume look suspicious. Shared hosting accounts also have hourly sending limits; marketing campaigns belong on a service designed for bulk email.
How IDX helps
IDX business email is set up with SPF and DKIM on your domain, and our support team can review your DNS and help you add DMARC. See also email client settings for connecting your mailbox correctly.
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