How to resolve Microsoft deliverability issues and IP blocks when using Salesforce Marketing Cloud?

Email marketer from Email on Acid suggests, you must clean your email list to prevent deliverability issues. Regularly remove invalid or inactive email addresses.

Email marketer from Gmass suggests you should avoid using URL shorteners, because they can often get flagged as spam.

Email marketer from Sendgrid suggests, if you are using a new dedicated IP address, you should warm it up. Start with small volumes of emails to your most engaged users and gradually increase the volume over time to build your sender reputation.

Email marketer from Email Vendor Selection shares that you need to segment your lists, personalise content, and use marketing automation to improve your email deliverability. It is also important to ensure CAN-SPAM compliance.

Email marketer from Reddit suggests if you're being blocked by Hotmail/Outlook, it is important to check your sender reputation and ensure your domain isn't on any blacklists. Also ensure that you're sending relevant content and not spamming users.

Email marketer from Mailjet suggests that you should check your sender score, review your sending infrastructure, and analyze your content to improve your email deliverability and not get flagged as spam. This includes making sure content isn't too spammy.

Email marketer from Email Geeks shares experience where sending images/links with HTTP caused Microsoft blocks. Fixing the HTTP links and then contacting SF support directly led to unblocking.

Email marketer from Litmus recommends using a dedicated IP address and warming it up. A dedicated IP address allows you to build your own sender reputation. Also, make sure you are following up with Microsoft's postmaster guidelines.

Email marketer from Stack Overflow shares that it is important to ensure the sending IP address is not blacklisted, configure SPF and DKIM records correctly for your domain and monitor the sending reputation with Microsoft SNDS.

Email marketer from Reddit suggests, when facing blocks despite good practices, using Microsoft's sender support form and being persistent in communication. Provide detailed information about your sending practices and request a review, especially if you have implemented SPF, DKIM, and DMARC.

Email marketer from Email Geeks advises being persistent with Microsoft support, even if they initially deny any issues, and pushing for more information to potentially get unblocked.

Expert from Email Geeks suggests it looks like an IP block on the SFMC IP range and SFMC's delivery team should manage this.

Expert from Word to the Wise shares that to maintain a good sender reputation with Microsoft, it's important to actively manage your subscriber lists by promptly removing invalid addresses and actively unsubscribing unengaged recipients. Also, always send wanted content and ensure it's easy to unsubscribe.

Expert from Email Geeks advises that if an S3150 bounce is happening consistently, it's a strong indication to push back on Microsoft and demand escalation.

Expert from Email Geeks explains that when Microsoft replies that they see no problem, it typically means the IP is blocked for a reason and needs fixing before moving forward; persistence and escalation might lead to re-evaluation.

Expert from Email Geeks explains that when receiving 4xx errors from SFMC it's typically DNS resolution issues, networking issues, MTA networking problems or hard blocks. You need to work with SFMC support to resolve.

Expert from Email Geeks asks for the specific error message to assist in diagnosing the deliverability issue.

Expert from Spam Resource explains that resolving Microsoft OLC (Outlook.com) blocking requires a multi-faceted approach. It begins with identifying the specific error messages, understanding whether the block affects all Microsoft users or a subset, checking IP and domain reputation using SNDS, ensuring proper authentication (SPF, DKIM, DMARC) and engaging proactively with Microsoft's support channels, providing detailed information about your sending practices and compliance efforts.

Expert from Email Geeks suggests obtaining the raw bounce message from Salesforce Support to help diagnose the Microsoft block, suggesting submitting the Microsoft form directly and leaning on Salesforce Support for assistance.

Documentation from Salesforce Help explains how to use Sender Authentication Package (SAP) in Marketing Cloud. SAP consists of dedicated IP address, custom domain authentication, and Reply Mail Management. It authenticates your emails and improves deliverability.

Documentation from Google Workspace explains that bulk email senders must authenticate their email using SPF, DKIM, and DMARC. In addition, it shares that you must keep spam rates reported in Postmaster Tools below 0.10% and avoid reaching a spam rate of 0.30% or higher.

Documentation from Salesforce Help recommends warming up the IP address gradually, segmenting email lists, cleaning your lists regularly (removing unengaged users), closely monitoring bounce rates and feedback loops and ensuring compliance with CAN-SPAM and other email marketing laws.

Documentation from Microsoft SNDS explains how to use the Smart Network Data Services (SNDS) to monitor the health and reputation of your sending IP addresses with Microsoft. SNDS can provide data on complaint rates, spam trap hits, and other metrics that affect deliverability.

Documentation from Microsoft Learn provides steps to troubleshoot blocked senders, advising to check the sender's IP or domain against blocklists, ensure proper authentication (SPF, DKIM, DMARC), and review sending practices to avoid spam filters. It also suggests using Microsoft's SNDS (Smart Network Data Services) to monitor IP reputation.

Documentation from Sparkpost explains that SPF, DKIM and DMARC records are required for deliverability. Also, they share that DNS records are critical for email deliverability. You need to correctly configure SPF, DKIM, and DMARC records to authenticate your emails.