How I got my business emails through spam filters with SPF, DKIM, and DMARC


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Kerry Wan/ZDNET

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ZDNET key takeaways

  • There are three DNS records that protect your domain and keep your emails out of junk.
  • Running all three gives you complete coverage. 
  • They also protect your domain from being hijacked.

If you send a lot of work emails and keep getting radio silence, your emails are very likely ending up in someone’s spam folder. 

There are a few reasons this could happen that don’t always have to do with the contents of your emails. Most commonly, your domain may not be authenticated, which gives receiving mail servers all the reason they need to quietly file your messages away in the spam folder. 

Also: How a burner email can protect your inbox – setting one up one is easy and free

I’ve seen this catch people off guard more often than you’d expect, including teams with genuinely good email content. Thankfully, there’s an easy fix involving three DNS records called SPF, DKIM, and DMARC. Together, they prove to the internet that your emails are legitimate. They also protect your domain from being hijacked by cybercriminals so they can impersonate you in emails.

Gmail and Yahoo began enforcing these authentication requirements for bulk senders in Feb. 2024. Following this, Microsoft added the same requirements for Outlook.com, Hotmail, and Live.com in May 2025. If you haven’t set these up yet, they are no longer optional.

What SPF, DKIM, and DMARC actually do

Each of the three protocols addresses a different weak point in email authentication. SPF verifies that the server sending your email is authorized to do so. DKIM adds a cryptographic signature to your outgoing messages, confirming they haven’t been altered in transit. 

DMARC ties the two together by publishing a policy that tells receiving servers what to do when either check fails, and routes authentication reports back to you.

You genuinely need all three. SPF alone can’t stop someone from forging the “From” address your recipient sees in their inbox. DKIM alone won’t catch an email sent from an unauthorized server. Only when you run all three do you get complete coverage against both deliverability problems and domain spoofing.

1. SPF: Authorize the servers that send on your behalf

screenshot-tool-20260521185856.png

Screenshot by Ritoban Mukherjee/ZDNET

SPF (Sender Policy Framework) is a DNS TXT record that lists every IP address and mail server authorized to send email on behalf of your domain. When a recipient’s mail server receives a message claiming to be from you, it checks that record against the sending server’s IP. If the IP isn’t on the list, the message fails.

Also: Here’s my favorite email trick for cleaning up inbox clutter – automatically

Setting it up means logging in to your domain registrar (GoDaddy, Cloudflare, Namecheap, etc.) and adding a TXT record at the root of your domain. Here’s how that works: 

  1. First get your SPF value from your email service. Google Workspace, Microsoft 365, and most platforms provide the exact record value you need to copy-paste on their domain authentication page. For Google Workspace, it goes like this: v=spf1 include:_spf.google.com ~all. 

  2. If you send emails through multiple services, you should stack them in the same record, e.g.  v=spf1 include:_spf.google.com include:spf.protection.outlook.com ~all. 

  3. Log into the platform where you manage your domain’s DNS records. This could be GoDaddy, Cloudflare, Namecheap, Route 53, etc. Create a new TXT record on your DNS page, set the host to @ (your root domain), and paste the SPF value from the earlier step.

It’s as easy as that! Note that your domain can have only one SPF TXT record, with no more than 10 DNS lookups. Creating a second SPF record instead of editing the first will break both. So keep your authorized senders list lean. 

2. DKIM: Add a tamper-proof signature to every email

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Screenshot by Ritoban Mukherjee/ZDNET

DKIM (DomainKeys Identified Mail) uses public-key cryptography to sign your outgoing messages. Your mail server attaches a signature using a private key it holds, so recipients can verify it against a matching public key you’ve published in your DNS. If the email was modified at any point between your server and the recipient’s inbox, that signature check fails.

Also: This simple email trick saves me from annoying marketing spam (and it’s free to do)

Google Workspace, Microsoft 365, and most major email platforms like SendGrid will generate a DKIM key pair for you. Your job is to copy the public key they provide and paste it into your domain’s DNS settings as a new TXT record. 

While the exact setup steps depend on your email provider and domain registrar, here’s a general overview of what you need to do. 

  1. Google Workspace, Microsoft 365, SendGrid, Mailchimp, and other email service providers will generate a DKIM record for you if you navigate to their domain authentication settings page. For example, if you use Google Workspace, this is located within Apps > Google Workspace > Gmail in Google Admin Console. Click to generate a new record and copy these values first. 

  2. Next, navigate to your domain registrar’s DNS settings page and create a new TXT record like you did when setting up SPIF earlier. Note that some providers may also require you to add this as a CNAME record instead of a TXT record, so refer to your email provider’s documentation. 

  3. Paste in the host name and record value you got from your email provider into the new DNS record. Make sure there are no typos because this can affect domain security.

  4. Now, return to your email provider’s authentication settings. This is where you enable DKIM signing for your domain. In Google Workspace, this is done by revisiting the “Authenticate email” page in the Admin Console and clicking “Start authentication.” Remember that you should do this after 24-48 hours since DNS records take a while to propagate across your domain. 

DKIM is especially useful for forwarded messages. Forwarding often breaks SPF because the IP address changes, but the DKIM signature typically survives intact. That means a forwarded email can still pass authentication when SPF alone would have failed. 

3. DMARC: Set the rules for what happens when authentication fails

screenshot-tool-20260521190257.png

Screenshot by Ritoban Mukherjee/ZDNET

DMARC (Domain-based Message Authentication, Reporting, and Conformance) is the policy layer that makes SPF and DKIM enforceable. Without it, a receiving server that detects a failed check has no instructions on what to do next, and you have no visibility into what’s failing or why. Here’s how to get it up and running:

  1. Start by creating a dedicated inbox for DMARC reports first, like reports@yourdomain.com. 

  2. Most email providers offer a DMARC generator in their dashboard, but you can also use a third-party service like MXToolbox or DMARCLY. 

  3. Add a new TXT record. The host name should read _dmarc. Paste in the record value directly from your DMARC generator. 

  4. Keep an eye out for any failure reports in your dedicated inbox for 2-4 weeks. This will reveal any issues with the mailbox that need to be addressed for better deliverability.

Also: I tested NordVPN’s free scam checker with real phishing emails – here’s how it fared

Like the other two, DMARC is a TXT record, added this time to _dmarc.yourdomain.com. A simple starting record looks like this: v=DMARC1; p=none; rua=mailto:reports@yourdomain.com. The p=none setting means receiving servers won’t take any action on failing messages, but will send you aggregate reports at the address you specify. Those reports show which services are sending on your behalf and whether they’re passing authentication.

Once you’ve reviewed a few weeks of reports and confirmed your legitimate mail is passing cleanly, you can tighten the policy. Move to p=quarantine to route failing messages to spam, then eventually to p=reject to block them entirely. 

Jumping straight to p=reject before reviewing your reports is probably the most common implementation mistake I see, and it ends up blocking your own marketing or transactional emails.

Why you can’t just pick one

Each protocol has a gap that the others fill. SPF checks the sending server but not the “From” address that recipients actually see, so an attacker can pass SPF while still impersonating your domain. DKIM verifies message integrity but doesn’t check whether the signing domain matches the visible sender. 

DMARC enforces alignment among all these elements and applies your chosen policy when something is out of alignment.

The combined deliverability upside is measurable. According to Validity’s 2025 Email Benchmark Report, properly authenticated domains see inbox placement rates roughly 60 percentage points higher than unauthenticated ones. For anyone running cold outreach campaigns or bulk newsletters, that gap is the difference between a campaign that produces results and one that disappears entirely.

How to verify your records are working

DNS changes typically take anywhere from 15 minutes to 48 hours to propagate worldwide. Once that window passes, free tools can tell you immediately whether everything is configured correctly. MX Toolbox has separate checkers for SPF, DKIM, and DMARC. You can also send a test email to check@dmarcly.com, which replies with a full authentication report for your domain.

Also: Best email hosting services 2026: Expert tested and reviewed

Your DMARC aggregate reports are the most valuable ongoing signal. Within a day or two of publishing your DMARC record, reports will start arriving at the address you specified. They show every server sending email under your domain and whether each one is passing or failing authentication. Reading them regularly is the best way to catch misconfigurations early, before they affect your deliverability or allow your domain to be abused in phishing campaigns.





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Recent Reviews


  • Law establishes national prohibition against nonconsensual online publication of intimate images of individuals, both authentic and computer-generated.
  • First federal law regulating AI-generated content.
  • Creates requirement that covered platforms promptly remove depictions upon receiving notice of their existence and a valid takedown request.
  • For many online service providers, complying with the Take It Down Act’s notice-and-takedown requirement may warrant revising their existing DMCA takedown notice provisions and processes.
  • Another carve-out to CDA immunity? More like a dichotomy of sorts…. 

On May 19, 2025, President Trump signed the bipartisan-supported Take it Down Act into law. The law prohibits any person from using an “interactive computer service” to publish, or threaten to publish, nonconsensual intimate imagery (NCII), including AI-generated NCII (colloquially known as revenge pornography or deepfake revenge pornography). Additionally, the law requires that, within one year of enactment, social media companies and other covered platforms implement a notice-and-takedown mechanism that allows victims to report NCII.  Platforms must then remove properly reported imagery (and any known identical copies) within 48 hours of receiving a compliant request.

Support for the Act and Concerns

The Take it Down Act attempts to fill a void in the policymaking space, as many states had not enacted legislation regulating sexual deepfakes when it was signed into law. The Act has been described as the first major federal law that addresses harm caused by AI. It passed the Senate in February of this year by unanimous consent and passed the House of Representatives in April by a vote of 409-2. It also drew the support of many leading technology companies.

Despite receiving almost unanimous support in Congress, some digital privacy advocates have expressed some concerns that the new notice-and-takedown mechanism could have some unintended consequences for digital privacy in general.  For example, some commentators have suggested that the statute’s takedown provision is written too broadly and lacks sufficient safeguards against frivolous requests, potentially leading to the removal of lawful content –especially given the short 48-hour time to act following a takedown request.  [Note: In 2023, we similarly wrote about abuses of the takedown provision of the Digital Millennium Copyright Act]. In addition, some have argued that the law could undermine end-to-end encryption by possibly forcing such companies to “break” encryption to comply with the removal process.  Supporters of the law have countered that private encrypted messages would likely not be considered “published” under the text of the statute (which uses the term “publish” as opposed to “distribute”).

Criminalization of NCII Publication for Individuals

The Act makes it unlawful for any person “to use an interactive computer service to knowingly publish an intimate visual depiction of an identifiable individual” under certain circumstances.[1] It also prohibits threats involving the publishing of NCII and establishes various criminal penalties. Notably, the Act does not distinguish between authentic and AI-generated NCII in its penalties section if the content has been published. Furthermore, the Act expressly states that a victim’s prior consent to the creation of the original image or its disclosure to another individual does not constitute consent for its publication.

New Notice-and-Takedown Requirement for “Covered Platforms”

Along with punishing individuals who publish NCII, the Take it Down Act requires covered platforms to create a notice-and-takedown process for NCII within one year of the law’s passage. Below are the main points for platforms to consider:

  • Covered Platforms. The Act defines a “covered platform” as a “website, online service, online application, or mobile application” that serves the public and either provides a forum for user-generated content (including messages, videos, images, games, and audio files) or regularly deals with NCII as part of its business.
  • Notice-and-Takedown Process. Covered platforms must create a process through which victims of NCII (or someone authorized to act on their behalf) can send notice to them about the existence of such material (including a statement indicating a “good faith belief” that the intimate visual depiction of the individual is nonconsensual, along with information to assist in locating the unlawful image) and can request its removal.
  • Notice to Users. Adding an additional compliance item to the checklist, the Act requires covered platforms to provide a “clear and conspicuous” notice of the Act’s notice and removal process, such as through a conspicuous link to another web page or disclosure.
  • Removal of NCII. Within 48 hours of receiving a valid removal request, covered platforms must remove the NCII and “make reasonable efforts to identify and remove any known identical copies.”
  • Enforcement. Compliance under this provision will be enforced by the Federal Trade Commission (FTC).
  • Safe Harbor. Under the law, covered platforms will not be held liable for “good faith” removal of content that is claimed to be NCII “based on facts or circumstances from which the unlawful publishing of an intimate visual depiction is apparent,” even if it is later determined that the removed content was lawfully published.

Compliance Note: For many online service providers, complying with the Take It Down Act’s notice-and-takedown requirement may warrant revising their existing DMCA takedown notice provisions and processes, especially if those processes have not been reviewed or updated for some time.  Many “covered platforms” may rely on automated processes (or a combination of automated efforts combined with targeted human oversight) to fulfill Take It Down Act requests and meet the related obligation to make “reasonable efforts” to identify and remove known identical copies.  This may involve using tools for processing notices, removing content and detecting duplicates. As a result, some providers should consider whether their existing takedown provisions should also be amended to address these new requirements and how they will implement these new compliance items on the backend using the infrastructure already in place for the DMCA.

What about CDA Section 230?

Section 230 of the Communications Decency Act (“CDA”), 47 U.S.C § 230, prohibits a “provider or user of an interactive computer service” from being held responsible “as the publisher or speaker of any information provided by another information content provider.” Courts have construed the immunity provisions in Section 230 broadly in a variety of cases arising from the publication of user-generated content. 

Following enactment of the Take It Down Act, some important questions for platforms are: (1) whether Section 230 still protects platforms from actions related to the hosting or removal of NCII; and (2) whether FTC enforcement of the Take It Down Act’s platform notice-and-takedown process is blocked or limited by CDA immunity. 

On first blush, it might seem that the CDA would restrict enforcement against online providers in this area, as decisions regarding the hosting and removal of third party content would necessarily treat a covered platform as a “publisher or speaker” of third party content. However, a deeper examination of the text of the CDA suggests the answer is more nuanced.

It should be noted that the Good Samaritan provision of the CDA (47 U.S.C § 230(c)(2)) could be used by online providers as a shield from liability for actions taken to proactively filter or remove third party NCII content or remove NCII at the direction of a user’s notice under the Take It Down Act, as CDA immunity extends to good faith actions to restrict access to or availability of material that the provider or user considers to be “obscene, lewd, lascivious, filthy, excessively violent, harassing, or otherwise objectionable.” Moreover, the Take It Down Act adds its own safe harbor for online providers for “good faith disabling of access to, or removal of, material claimed to be a nonconsensual intimate visual depiction based on facts or circumstances from which the unlawful publishing of an intimate visual depiction is apparent, regardless of whether the intimate visual depiction is ultimately determined to be unlawful or not.” 

Still, further questions about the reach of the CDA prove more intriguing. The Take It Down Act appears to create a dichotomy of sorts regarding CDA immunity in the context of NCII removal claims.  Under the text of the CDA, it appears that immunity would not limit FTC enforcement of the Take It Down Act’s notice-and-takedown provision affecting “covered platforms.” To explore this issue, it’s important to examine the CDA’s exceptions, specifically 47 U.S.C § 230(e)(1).   

Effect on other laws

(1) No effect on criminal law

Nothing in this section shall be construed to impair the enforcement of section 223 or 231 of this title [i.e., the Communications Act], chapter 71 (relating to obscenity) or 110 (relating to sexual exploitation of children) of title 18, or any other Federal criminal statute.

Under the text of the CDA’s exception, Congress carved out Section 223 and 231 of the Communications Act from the CDA’s scope of immunity.  Since the Take It Down Act states that it will be codified at Section 223 of the Communications Act of 1934 (i.e., 47 U.S.C. 223(h)), it appears that platforms would not enjoy CDA protection from FTC civil enforcement actions based on the agency’s authority to enforce the Act’s requirements that covered platforms “reasonably comply” with the new Take It Down Act notice-and-takedown obligations.

However, that is not the end of the analysis for platforms.  Interestingly, it would appear that platforms would generally still retain CDA protection (subject to any exceptions) from claims related to the hosting or publishing third party NCII that have not been the subject of a Take It Down Act notice, since the Act’s requirements for removal of NCII by platforms would not be implicated without a valid removal request.[2]  Similarly, a platform could make a strong argument that it retains CDA immunity from any claims brought by an individual (rather than the FTC) for failing to reasonably comply with a Take It Down Act notice.  That said, it is conceivable that litigants – or event state attorneys general – might attempt to frame such legal actions under consumer protection statutes, as the Take It Down Act states that a failure to reasonably comply with an NCII takedown request is an unfair or deceptive trade practice under the FTC Act.  Even in such a case, platforms would likely contend that such claims by these non-FTC parties are merely claims based on a platform’s role as publisher of third party content and are therefore barred by the CDA. 

Ultimately, most, if not all, platforms will likely make best efforts to reasonably comply with the Take It Down Act, thus avoiding the above contingencies.  Yet, for platforms using automated systems to process takedown requests, unintended errors may occur and it’s important to understand how and when the CDA would still protect platforms against any related claims.

Looking Ahead

It will be up to a year before the notice-and-takedown requirements become effective, so we will have to wait and see how well the process works in eradicating revenge pornography material and intimate AI deepfakes from platforms, how the Act potentially affects messaging platforms, how aggressively the Department of Justice will prosecute offenders, and how closely the FTC will be monitoring online platforms’ compliance with the new takedown requirements.

It also remains to be seen whether Congress has an appetite to pass more AI legislation. Less than two weeks before the Take it Down Act was signed into law, the Senate Committee on Commerce, Science, and Transportation held a hearing on “Winning the AI Race” that featured the CEOs of many well-known AI companies. During the hearing, there was bipartisan agreement on the importance of sustaining America’s leadership in AI, expanding the AI supply chain and not burdening AI developers with a regulatory framework as strict as the EU AI Act. The senators listened to testimony from tech executives calling for enhanced educational initiatives and the improvement of infrastructure needed for advancing AI innovation, alongside discussing proposed bills regulating the industry, but it was not clear whether any of these potential policy solutions would receive enough support to be signed into law.

The authors would like to thank Aniket C. Mukherji, a Proskauer legal assistant, for his contributions to this post.


[1] The Act provides that the publication of the NCII of an adult is unlawful if (for authentic content) “the intimate visual depiction was obtained or created under circumstances in which the person knew or reasonably should have known the identifiable individual had a reasonable expectation of privacy,” if (for AI-generated content) “the digital forgery was published without the consent of the identifiable individual,” and if (for both authentic and AI-generated content) what is depicted “was not voluntarily exposed by the identifiable individual in a public or commercial setting,” “is not a matter of public concern,” and is intended to cause harm or does cause harm to the identifiable individual. The publication of NCII (whether authentic or AI-generated) of a minor is unlawful if it is published with intent to “abuse, humiliate, harass, or degrade the minor” or “arouse or gratify the sexual desire of any person.” The Act also lists some basic exceptions, such as publications of covered imagery for law enforcement investigations, legal proceedings, or educational purposes, among other things.

[2] Under the Act, “Upon receiving a valid removal request from an identifiable individual (or an authorized person acting on behalf of such individual) using the process described in paragraph (1)(A)(ii), a covered platform shall, as soon as possible, but not later than 48 hours after receiving such request—

(A) remove the intimate visual depiction; and

(B) make reasonable efforts to identify and remove any known identical copies of such depiction.



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