Fix Gmail Email Rejection Caused by DNS PTR Issues

You may feel frustrated when Gmail refuses to accept your emails because of DNS PTR record problems. Many users now see more rejections from Gmail as Google enforces strict sender requirements, especially when sending from overseas infrastructure such as Japan hosting environments. You might notice error code 550-5.7.25, which points to missing PTR records. These DNS issues cause real obstacles for your email delivery, whether your server is located locally or on a Japan hosting platform. If you want to restore reliable communication, you need to address these problems step-by-step.

Key Takeaways

• Check Gmail error messages to identify issues with your email delivery. Look for codes like 550-5.7.25 that indicate missing PTR records.

• Verify your PTR record using tools like EasyDMARC or the nslookup command. Ensure your sending IP has a valid PTR record to avoid rejections.

• Match your PTR and A records to improve email deliverability. Conduct both reverse and forward DNS lookups to confirm they align.

• Regularly monitor your DNS settings and PTR records. Set reminders to check every few months to prevent future email delivery issues.

• Update your DNS settings promptly if you find mismatches. Proper configuration helps maintain your sender reputation and ensures emails reach inboxes.

Fix Gmail PTR Record Issues

Identify Gmail Error Messages

When Gmail refuses to accept your email, you often see specific error messages. These messages help you understand the root cause of the problem. You should always check the bounce-back or rejection notice for clues. The most common Gmail error codes related to PTR record failures appear in the table below:

You may also see this code:

If you notice these errors, you know that Gmail refuses to accept your email because of DNS or PTR issues.

Check PTR Record for Sending IP

You need to verify the PTR record for your sending IP address. This step helps you confirm if your DNS is set up correctly. You can use several tools to check PTR records:

• EasyDMARC’s PTR Checker lets you enter your domain or IP address and view results quickly.

• DMARC DKIM PTR Reverse IP Lookup allows you to enter an IP address for a PTR lookup.

• The nslookup command in Command Prompt or Terminal checks PTR records.

To use the command line:

1. Open Command Prompt or Terminal.

2. Type nslookup <IP_address> or dig <domain> ptr.

3. Review the PTR records listed in the output.

If you use multiple outbound IP addresses for email, check each one. Gmail may block messages from any IP without a valid PTR record.

Match PTR and A Records

You must ensure that your PTR and A records match. This process involves two main steps:

1. Perform a reverse DNS lookup to find the domain name associated with your IP address using the PTR record.

2. Conduct a forward DNS lookup on the resulting domain name to see if it resolves back to the original IP address.

Mismatching between PTR and A records can lead to significant issues with email deliverability, particularly affecting acceptance rates by Gmail and other email providers. If the PTR record does not resolve correctly to the sending domain or does not match the A record, it can result in emails being rejected or marked as spam, thereby harming the sender’s reputation and delivery rates.

Many mail servers may reject connections from IP addresses without PTR records, leading to immediate delivery failures. Over time, missing PTR records can damage your sender reputation.

Update DNS Settings

If you find problems with your PTR or A records, you need to update your DNS settings. Follow these steps:

1. Select “Dynamically update DNS A and PTR records only if requested by DHCP clients.” This ensures that A records are registered by the client and PTR records by DHCP.

2. Set the necessary credentials in the DHCP Console to allow proper registration.

3. Remove the DHCP server from the DNSUpdateProxy Group on the DNS server.

4. Check if the changes resolve the PTR record issues.

You may also need to:

• Disable antivirus software on the domain controller to rule out interference.

• Ensure the checkbox “Discard A and PTR records when lease is deleted” is selected to manage DHCP leases effectively.

DNS changes can take time to propagate. The table below shows typical propagation times:

You should wait for full propagation before testing email delivery.

Test Email Delivery

After updating your DNS and PTR records, you need to test email delivery. Use these methods:

• Use safe testing tools like Mailtrap Email Testing to inspect and debug emails without spamming users.

• Check deliverability by analyzing spam reports that provide an overall spam score and detailed test points.

• Verify your IP address against common blacklists to identify any issues that may affect email delivery.

Send test emails to Gmail accounts and monitor for bounce-backs or spam folder placement. If Gmail refuses to accept your email again, repeat the steps above to find and fix any remaining DNS or PTR issues.

Tip: Regularly monitor all outbound IP addresses if your organization uses more than one. This practice helps you catch DNS or PTR problems before they impact your email delivery.

PTR Record Basics for Gmail

What Is a PTR Record?

You may wonder what a PTR record is and why it matters for your email. A PTR record, also called a Pointer Record, is a special type of DNS entry. It links an IP address to a domain name. This process is known as reverse DNS lookup. When you send an email, the receiving server uses the PTR record to check if your IP address matches the domain you claim to send from. This step helps verify your identity and builds trust with other email servers.

• A PTR record verifies the sender’s IP address against the claimed domain.

• It allows reverse DNS lookups, translating IP addresses into domain names.

• It strengthens email security by making it harder for attackers to spoof your address.

If you do not have a correct PTR record, your emails may not reach their destination.

Why Gmail Requires PTR Records

Gmail uses PTR records as a key part of its security checks. You need a valid PTR record so Gmail can confirm that your hostname matches your sending IP address. This process, called Forward Confirmed reverse DNS (FCrDNS), helps stop email spoofing. Anyone can create a domain, but not everyone can set up a matching PTR record. Gmail wants to see that your PTR record exists and points back to your IP address. This requirement protects users from fake emails and keeps spam out of inboxes.

Note: Gmail will reject or rate limit your email if your PTR record does not match your sending IP address.

How PTR Records Affect Email

PTR records play a big role in email deliverability. If you have missing PTR records or incorrect entries, you will face problems. Many users report that their emails to Gmail get blocked or delayed because of PTR issues. In fact, missing or incorrect PTR records cause most delivery failures. When your PTR record is wrong, Gmail may mark your email as spam or reject it completely. This can hurt your sender reputation and even lead to blacklisting.

• Reverse DNS checks help filter out spam.

• Errors with PTR records can cause legitimate emails to be rejected.

• Accurate PTR records confirm your identity and improve your chances of reaching the inbox.

You should always check your PTR records to make sure your email gets delivered to Gmail users.

Email DNS Matching Issues

Forward vs. Reverse DNS

You need to understand the difference between forward and reverse DNS to keep your email flowing smoothly. Forward DNS takes a domain name and finds its IP address. Reverse DNS lookup does the opposite—it starts with an IP address and finds the domain name. Both play a big role in email delivery. If these records do not match, gmail may block or flag your messages.

A failed reverse DNS lookup is one of the top reasons your email lands in the spam folder. Without a valid PTR record, the receiving server cannot verify your identity and may block your email.

Common DNS Mismatches

Many issues can cause gmail to reject your email. You might use a VPS and forget to change the default PTR record. Sometimes, you update your DNS records but do not adjust your mail software settings. If you share an IP address, your provider may set the PTR to their own domain, not yours. You may also lack permission to change the PTR record if your ISP controls the IP. Other common problems include SPF records with too many DNS lookups, missing DKIM selectors, or a misaligned Return-Path.

Tip: Always check your PTR, SPF, DKIM, and MX records after any change to your email setup.

Ensuring Consistency

You can troubleshoot and fix DNS mismatches by following a few steps:

1. Verify your server’s IP resolves to your domain using tools like MXToolbox.

2. Contact your ISP to add a PTR record that matches your forward DNS A record.

3. Make sure your A and PTR records align perfectly to avoid delivery issues.

4. Update MX records to match your email hosting provider’s values.

5. Add an SPF record to list authorized mail sources.

6. Set up DKIM for outbound email signing.

7. Configure a DMARC record to monitor authentication.

You should review your DNS records every three to six months, especially after switching platforms or adding new services. Regular checks help prevent gmail from rejecting your email due to reverse DNS lookup failures.

Gmail PTR Policy & Prevention

Gmail’s PTR Record Policy

You must understand gmail requirements for sending email. Gmail expects every sending server to have a valid ptr record. This rule helps confirm the legitimacy of your email server. If your server lacks proper dns settings, gmail may block your messages. The table below summarizes the main requirements:

You may see error code 550 5.7.25 if your server does not meet these standards. This code means gmail has blocked your email because your IP does not have a valid ptr record.

How PTR Failures Cause Rejection

Gmail uses dns checks to protect users from spam and phishing. When you send email, gmail looks for a ptr record that matches your sending IP. If the ptr record is missing or incorrect, gmail cannot confirm your server’s identity. This failure makes your server look suspicious. Gmail then rejects your email to prevent possible abuse. Reliable dns settings show that your server is trustworthy. Without them, you risk email rejections and delivery problems.

Ongoing Monitoring Checklist

You can prevent most ptr-related issues by monitoring your dns records regularly. Use this checklist to keep your email flowing smoothly:

• Ensure a ptr record exists for your sending IP.

• Verify that the ptr hostname resolves back to the same IP (forward-confirmed reverse dns).

• Check that the hostname matches or relates to your sending domain.

Ongoing monitoring helps you catch problems early. You can adjust your settings, investigate root causes, and avoid email rejections. Proactive checks keep your email reputation strong and your messages reaching inboxes.

Tip: Set calendar reminders to review your dns and ptr records every few months. This habit helps you stay ahead of potential issues.

When gmail refuses to accept your email, you need to act fast. Start by checking your dns and PTR records. Follow these steps to ensure reliable email delivery:

1. Match the PTR record with your server hostname to prevent email from being marked as spam.

2. Set your server hostname using sudo hostnamectl set-hostname mail.example.com.

3. Verify the hostname with the hostname command.

4. Contact your provider to update the PTR record if you cannot do it yourself.

5. Use dig -x 1.2.3.4 +short to check the current PTR record.

Regularly monitor your dns and PTR records. This habit helps you avoid issues when gmail refuses to accept your email.

FAQ

What happens if I do not set a PTR record for my mail server?

Gmail may reject your emails or send them to spam. You need a PTR record to prove your server’s identity. This record helps Gmail trust your messages.

How do I know if my PTR record is correct?

You can use tools like MXToolbox or the nslookup command. Enter your IP address and check if the result matches your mail server’s domain name.

Can I set a PTR record myself?

Usually, you cannot set a PTR record directly. You must contact your hosting provider or ISP. Ask them to update the PTR record for your server’s IP address.

How long does it take for PTR record changes to update?

DNS changes, including PTR records, may take from a few minutes up to 48 hours to update worldwide. You should wait before testing email delivery again.