On April 2, 2025, Microsoft Outlook announced new requirements for bulk senders. This follows in the footsteps of the previous Gmail and Yahoo requirements.

Review new Microsoft requirements and best practices.

On October 3, 2023, both Gmail and Yahoo announced updates to their sender requirements to minimize spam and phishing emails with the intention of improving the overall experience of Gmail and Yahoo Mail subscribers. These changes will go into effect in February 2024, a significant stride in ensuring a safer and more secure email environment for all users.

We recently shared best practices for sending success. If you are complying with these email practices, aligning with the new requirements should be seamless.

Here’s a look at what’s changing, how Acoustic is addressing the changes, and easy steps so you can continue sending emails without disruption.

Review setup and ensure domain authentication

What’s changing: Starting February 2024, Gmail and Yahoo will require domain-aligned authentication with DKIM (DomainKeys Identified Mail) and SPF (Sender Policy Framework), and they will be enforcing DMARC (Domain-based Message Authentication, Reporting & Conformance) policies. These new protocols will offer an added layer of email security that helps prevent email spoofing and phishing attacks.

Other considerations for setup include ensuring that sending domains or IPs have valid forward and reverse DNS records, also referred to as PTR records.

How Acoustic has you covered: As part of our domain provisioning process, we automatically set up SPF, DKIM, and PTR for Acoustic-hosted customer domains and we will add a DMARC record into your DNS. We’re also actively in the process of validating all of our customers’ DKIM keys and making sure they’re technically compliant with the new standards.

For customer domains NOT hosted by Acoustic, senders will be required to set up DMARC. For further details on DMARC policy, and how to validate compliance or setup, read our DMARC help article. If you require consulting services for DMARC, contact your Acoustic Customer Success Manager for details on our Deliverability Services offerings.

As part of Acoustic’s domain provisioning process, we automatically setup and provide PTR / RDNS for Acoustic client domains. If you would like to see if your rDNS is valid, you can use a tool such as https://multirbl.valli.org/fcrdns-test/, and enter your sending IP address(es). If the results are green, you are setup correctly. If you see red, or failures, contact Acoustic Support.

Setup easy unsubscribe

What’s changing: Marketing messages and subscribed messages must support one-click unsubscribe (through list-unsubscribe in the email headers) and include a clearly visible unsubscribe link (per global spam laws) in the message body to allow email recipients an easy way to opt out of mailings. Additionally, Gmail and Yahoo will require senders to process the unsubscribe request within two days. Global legislation can vary on the length of time required to honor an unsubscribe request.

Pro tip: We recommend addressing requests to be removed as soon as possible to help protect your sending reputation.

How Acoustic has you covered: Acoustic supports one click unsubscribe via headers for emails that have secure links and images (SSL). If your company’s sending domain is not setup with SSL (think: https links), Acoustic will reach out to begin the setup process.

Monitor spam rates

What’s changing: Spam rate thresholds will be enforced with a maximum complaint rate of 0.3%. If you consistently send emails with a high spam rate, your messages may be rejected or sent to the spam folder.

How Acoustic has you covered: We can help ensure you are sending emails to your most active and engaged customers. The best way to do this is by keeping content relevant to your intended audience and setting expectations with them so they’re looking for messages to come through. For those sending to Gmail, you can use Google Postmaster Tools to monitor reputation and spam compliance rates. More instructions on how to setup Google postmaster for Acoustic-hosted domains and client hosted domains is available here and listed below.

To setup Google Postmaster Tools for Acoustic-hosted domains:

1. Open a support case with Acoustic to raise the request.
2. Grant access to your Acoustic-hosted domain’s Google Postmaster Tools account.
3. Ensure you provide the Google hosted email address that you use to sign-in to Google Postmaster Tools.
4. Once you receive confirmation from our Acoustic Support team, add the domain in Google Postmaster Tools.
5. Click Add domain and enter the domain name for which you have obtained permission to manage. Then click Verify.

To setup Google Postmaster Tools for client-hosted domains:

1. Create or use an existing Google account. You’ll use this account to access Google Postmaster Tools.
2. Access Google Postmaster Tools and sign in with your Google account.
3. Provide the domain that you use for sending the emails by clicking Add domain and enter the domain name for which you have obtained permission to manage.
4. Next, you must verify ownership of the domain. Copy the TXT record provided in the Domain verification screen.
5. Provide this information to the domain’s administrator or the individual who has access to the domain’s DNS settings to add the TXT record to their DNS configuration.
6. After the DNS record is added, click verify to proceed with the verification process in Google Postmaster Tools. It might take some time for DNS changes to propagate, so verification may not be immediate.

Additional considerations and practices

Format messages according to the Internet Message Format standard (RFC 5322). RFC 5322 is essential for email communication, setting the standard for email format and ensuring consistency across various systems and software. Acoustic rigorously follows this specification, ensuring all our emails meet its established standards.

Don’t impersonate Gmail’s (or any other ISP or company) headers or pretend to be a sender that you’re not. Gmail will begin using a DMARC quarantine enforcement policy, and impersonating Gmail From: headers might impact your email delivery.