Common Issues & Solutions

Emails fail SPF checks, or you see "SPF PermError - too many DNS lookups" in headers.

• No SPF record: Add a TXT record to your DNS like: v=spf1 include:_spf.google.com ~all
• Too many lookups: SPF has a 10-lookup limit. Use our SPF Checker to count lookups and flatten your record
• Multiple records: You can only have ONE SPF record per domain - combine them into a single record

DKIM checks fail, or no DKIM signature is present in email headers.

• Not signing: Enable DKIM signing in your email service provider (Gmail, SendGrid, Mailchimp, etc.)
• DNS record missing: Publish the DKIM public key as a TXT record (usually at selector._domainkey.yourdomain.com)
• Key too short: Use at least 1024-bit keys (2048-bit recommended for security)
• Selector mismatch: The selector in the email signature must match the DNS record name

No DMARC record exists, or DMARC checks show "not aligned" despite passing SPF/DKIM.

• No policy: Create a DMARC record at _dmarc.yourdomain.com, start with: v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com
• Domain mismatch: Ensure From domain matches SPF envelope domain or DKIM d= domain
• Subdomain issues: Add DMARC records for subdomains or use sp= policy in parent domain

Emails are delivered but land in spam/junk folders instead of inbox.

• Fix authentication: Ensure SPF, DKIM, and DMARC all pass
• Check blocklists: Use our Blocklist Checker to see if you're listed
• Improve content: Avoid spam trigger words, excessive links, and misleading subject lines
• Build engagement: Send to engaged subscribers who open and click your emails
• Add List-Unsubscribe: Include unsubscribe headers (required by Gmail/Yahoo for bulk senders)
• Warm up IPs: Gradually increase sending volume when using new IPs

PTR lookup fails or returns a different domain than expected.

• Set up PTR record: Contact your server/IP provider to set up reverse DNS pointing to your mail server hostname
• Match forward DNS: Ensure PTR record matches an A record for your domain
• Use provider's domain: If you can't control PTR, use your ESP's domain for SPF/DKIM instead

Many emails bounce back as "user unknown" or "mailbox full".

• Validate emails: Use email validation to catch typos and invalid addresses before sending
• Remove hard bounces: Immediately remove addresses that hard bounce (user not found)
• Monitor soft bounces: Retry soft bounces (mailbox full, server down) but remove after 3-5 attempts
• Clean old lists: Remove subscribers who haven't engaged in 6-12 months
• Double opt-in: Use double opt-in to ensure email addresses are valid and owned

Emails are rejected or heavily filtered, bounce messages mention blocklists.

• Check listings: Use our Blocklist Checker to find which lists you're on
• Fix the issue: Address the root cause (spam complaints, hacked server, compromised account)
• Request delisting: Visit each blocklist's website and follow their removal process
• Wait it out: Some lists automatically remove IPs after 24-48 hours of clean sending
• Get a new IP: If reputation is severely damaged, consider a fresh IP address