If you run a business in Milton Keynes, you've likely noticed a frustrating trend recently: invoices going ignored, booking confirmations landing in junk folders, or client replies bouncing back entirely. This isn't bad luck—it's the result of strict, automated email sender rules rolled out by Google and Yahoo/Microsoft.
The 0.3% Rule: Why Google is Blocking You
Google and Yahoo have implemented a strict **0.3% spam complaint rate threshold**. If just 3 out of every 1,000 emails you send are marked as spam or junk by the recipients, Google will automatically start blocking or throttling all emails coming from your domain.
But even if you are sending legitimate, requested business communications, your emails can still go straight to spam if your domain lacks proper authentication records. In 2026, without these records, your emails look like phishing attempts to automated filters.
The Three Pillars of Email Authentication
To prevent your domain from being flagged, you need to configure three specific DNS records at your domain registrar. Think of these as a digital passport for your domain:
1. SPF (Sender Policy Framework)
An SPF record is a list on your domain name configuration that explicitly tells mail servers which servers (like Google Workspace, Microsoft 365, or Mailchimp) are actually allowed to send emails on your behalf.
2. DKIM (DomainKeys Identified Mail)
DKIM acts as a digital signature. It cryptographically signs every email you send with a secure key, proving to the receiving server that the email wasn't tampered with or forged in transit.
3. DMARC (Domain Message Authentication & Reporting)
DMARC is the instruction manual. It tells Gmail or Outlook exactly what to do if an email fails the SPF or DKIM check (either do nothing, quarantine it in spam, or reject it outright), and sends you reports of failures.
How Milton Keynes SMEs Can Check Their Status
You don't need to be an IT guru to find out if your setup is broken. We have created a completely free diagnostic checker to test your domain for these records.
Simply head to our Free Email Health Checker and enter your domain. It will scan your DNS settings instantly and flag any missing authentication blocks.
Practical Next Steps
- Consolidate your senders: Audit all platforms sending emails under your domain (accounting software like Xero, CRM tools, booking systems).
- Update SPF: Ensure Xero or other platforms are explicitly included in your SPF DNS record.
- Enable DKIM: Generate and add DKIM public keys from your Google Workspace or Microsoft 365 admin portals.
- Start DMARC gently: Deploy a basic
p=none(monitoring only) policy before hardening it to avoid blocking legitimate emails.
Email Health Setup
Are your invoices going to junk?
We help local Milton Keynes businesses set up robust email authentication (SPF, DKIM, DMARC) to ensure their emails reach customers. Get in touch to clean up your deliverability.
Request Email Audit