What should a small MSP check when Google flags their domain for bad reputation?
Michael Ko
Co-founder & CEO, Suped
Published 8 Oct 2025
Updated 8 Oct 2025
6 min read
When Google flags a domain for bad reputation, it can feel like a sudden, severe blow, especially for a small Managed Service Provider (MSP) with limited resources. Emails crucial for client communication and business operations might suddenly stop reaching their destinations. This situation indicates that Google's systems perceive your domain as a source of potentially unwanted or suspicious email traffic, leading to blocks or delivery to spam folders.
Navigating this issue requires a systematic approach, starting with diagnosis and moving through remediation steps. Focusing on key areas like email authentication, sending practices, and monitoring can help restore your domain's health and ensure your messages reach the inbox.
Using Google Postmaster Tools
The first and most critical step for any MSP facing a bad domain reputation with Google is to utilize Google Postmaster Tools. This free tool provides invaluable insights directly from Google about your sending domain's performance. It will show you why Google views your domain unfavorably, often indicating issues like spam rates, IP reputation, and domain reputation scores as 'Bad', 'Low', 'Medium', or 'Good'.
To get started, simply add and verify your domain. Once verified, you can access dashboards for spam rate, domain reputation, and IP reputation. These metrics offer a clear picture of how Google perceives your email sending. For instance, a high spam rate might indicate that your recipients are frequently marking your emails as spam, while a low domain reputation signals systemic issues.
Regularly monitoring these dashboards is crucial for identifying trends and quickly addressing any new problems. It provides the foundational data you need before diving into specific technical or content-related fixes. This proactive approach helps in maintaining a good domain reputation over time.
Checking authentication records and infrastructure
Even for small MSPs, solid email authentication is non-negotiable. Google (and Yahoo) have new sender requirements that mandate proper SPF, DKIM, and DMARC setup. Start by verifying that your Sender Policy Framework (SPF) record correctly lists all authorized sending IPs and domains. Your DomainKeys Identified Mail (DKIM) signature should be properly configured and signing all outbound emails. Finally, ensure you have a DMARC record in place, ideally with a policy of p=quarantine or p=reject after a monitoring period.
Incorrect authentication can immediately flag your domain as suspicious. For example, an SPF DNS timeout or a DKIM mismatch can lead to emails being rejected outright. Ensuring all these protocols are correctly implemented and aligned is fundamental for establishing trust with mailbox providers. Suped offers robust DMARC monitoring to help you visualize and troubleshoot these issues effectively.
Good authentication practices
SPF: All legitimate sending sources are explicitly included in the record. The record does not exceed the 10-lookup limit.
DKIM: Emails are consistently signed by an authorized DKIM key that aligns with the sending domain. Avoid DKIM temporary errors.
DMARC: A policy is published (even at p=none to start) with reporting enabled. This provides visibility into your email ecosystem.
Risky authentication practices
SPF: Missing authorized senders, exceeding lookup limits, or using +all allows spammers to spoof your domain.
DKIM: Incorrect or missing DKIM records, or expired keys. A lack of alignment with the From: domain is also an issue.
DMARC: No record or an improperly configured record. A missing DMARC policy leaves your domain vulnerable to impersonation and phishing attacks.
Also consider the infrastructure your MSP uses. If it's a small operation, they might be relying on a less robust email sending solution. Google is known to be particularly fussy about IPv6, especially for senders with a nascent reputation. If you are sending via Microsoft 365, some users have found that disabling IPv6 for email delivery can sometimes alleviate issues with Gmail, although this is a controversial step.
Reviewing content and sending practices
Even with perfect authentication, poor sending practices can quickly tank a domain's reputation. For a small MSP, even a small number of spam complaints can have a disproportionate impact. Review the types of emails being sent and to whom. Are there any unsolicited marketing emails? Are email lists regularly cleaned to remove inactive or invalid addresses? High bounce rates and a significant number of spam complaints are red flags for Google.
Consider the content of the emails. Are they highly promotional, contain suspicious links, or use common spam trigger words? For an MSP, most emails should be transactional or client-service related, which typically have lower spam complaint rates. If the MSP is engaged in any form of outbound sales or cold emailing, those activities should ideally be separated onto a different domain or using a dedicated sending service to protect the primary domain's reputation.
Best practices for small senders
List hygiene: Regularly clean your email lists to remove inactive or invalid addresses. Avoid sending to old, unengaged contacts.
Consent: Only send emails to recipients who have explicitly opted in. Avoid purchased lists.
Content: Ensure email content is relevant, clear, and avoids spam trigger words. Personalize emails where possible.
Monitoring: Keep an eye on your domain health and adjust sending practices as needed. Use DMARC reports to identify issues.
Advanced troubleshooting and recovery
If, after checking authentication and content, the domain reputation remains 'Bad', it might be time to investigate further. Your domain or its associated IP addresses could be listed on a public blocklist (or blacklist). While Google Postmaster Tools provides reputation metrics, a blocklist check offers a more direct indicator of external perception. Services like Suped's blocklist monitoring can help identify if your domain or IP is listed on a major blocklist.
If your domain or IP is found on a blocklist, you'll need to follow the specific delisting procedures for each list. This usually involves resolving the underlying issue that caused the listing (e.g., spamming, compromised server) and then submitting a request. Additionally, if the domain is using Microsoft 365, investigate if there's any indication of a compromised server or account sending spam without the MSP's knowledge. Such compromises can severely damage reputation quickly.
After implementing all corrective measures, use the Google bulk sender escalation form to inform Google that you've addressed the issues. Recovery takes time, often weeks or even months of consistent, good sending practices to rebuild trust. Continuously monitor your domain reputation with Gmail through Postmaster Tools and DMARC reports to track progress.
Views from the trenches
Best practices
Always meet Google and Yahoo's email sender authentication requirements for SPF, DKIM, and DMARC.
Regularly monitor your domain's health using Google Postmaster Tools for any reputation dips or spam spikes.
Maintain strict list hygiene by cleaning out unengaged or old email addresses from your sending lists.
Segment email sending based on purpose, using different domains or services for cold outreach to protect your primary domain.
Ensure all outgoing email content is relevant, expected, and free of spam-triggering elements.
Common pitfalls
Ignoring Google Postmaster Tools, thus missing early warnings about reputation issues.
Sending unsolicited emails or using purchased lists, leading to high spam complaint rates and reputation damage.
Neglecting email authentication (SPF, DKIM, DMARC), making the domain vulnerable to spoofing and email rejection.
Not checking for compromised accounts or servers, which can unknowingly send spam and tank domain reputation.
Failing to adapt sending infrastructure to Google's specific requirements, such as stricter IPv6 handling.
Expert tips
Use DMARC reports from Suped to gain comprehensive insight into email authentication failures and potential abuse.
For small senders, even a few cold leads can severely impact domain reputation. Focus on highly engaged audiences.
If using M365 and experiencing IPv6 related issues with Gmail, consider disabling IPv6 for email sending if possible.
When issues are corrected, leverage Google's bulk sender escalation form to proactively inform them of your remediation efforts.
Understand that rebuilding a bad domain reputation takes consistent good sending practices and patience.
Expert view
An expert from Email Geeks says that basic authentication protocols are the first thing to check to ensure compliance with sender requirements.
2025-10-01 - Email Geeks
Marketer view
A marketer from Email Geeks suggests that a very low reputation message points directly to issues with the sending domain, and one should investigate if the sender's sales teams are sending unsupervised emails.
2025-10-01 - Email Geeks
Summary of key actions
When Google flags your MSP's domain for bad reputation, it's a call to action to review and optimize your email practices. By systematically checking Google Postmaster Tools, strengthening email authentication (SPF, DKIM, and DMARC with Suped's DMARC monitoring), refining sending content, and monitoring for blocklist entries, you can effectively diagnose and remediate issues. Remember that rebuilding trust with mailbox providers takes consistent effort and good sending habits. Proactive monitoring is the key to long-term email deliverability success.
Also consider the infrastructure your MSP uses. If it's a small operation, they might be relying on a less robust email sending solution. Google is known to be particularly fussy about IPv6, especially for senders with a nascent reputation. If you are sending via Microsoft 365, some users have found that disabling IPv6 for email delivery can sometimes alleviate issues with Gmail, although this is a controversial step.
