Showing posts with the label zmainfeature

Subdomains: What are they, and do you need them?

Subdomains are “sub entries” under your domain name. Sometimes they’re more accurately called hostnames or FQDNs (“fully qualified domain names”) but for simplicity's sake, I’m mostly just going to call them subdomains here. You're reading this on Spam Resource, which has a website address of www.spamresource.com, of which spamresource.com is the domain name. If I were going to creat…
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Do image-only emails harm deliverability?

This is a question that I get asked often: If somebody sends an email message that is 100% images, does that design choice itself make the message more likely to get relegated to the spam folder? My short answer is no, not really, but it merits a discussion, so let's dive …

History repeating: a quick lesson about apples and opting out

Jennifer Nespola Lantz's recent post about Gmail potentially offering political senders a fast pass method to the inbox has gotten me thinking about the spam fight we went through back in the olden times. Before CAN-SPAM, domain reputation and deliverability best practice…

B2B spam filters and domain blocking: Who blocked my mail?

Let's compare B2C versus B2B deliverability issues, shall we? In the B2C (business-to-consumer) or DTC (direct-to-consumer) email marketing universe, the number of mailbox providers, while broad, is very heavily concentrated in the US. There are six providers, that when you…

Let's track Apple MPP opens

Okay, they're not really opens. They're proxy-based, false positive pre-loaded opens. Don't think of them as opens. Think of them as something you want to get out of the way so as to not inflate your campaign tracking. I know, I know... Apple is not the only one pro…

Email Message Header & Message Checking Tools (2022 Update)

(Here's an updated version of a post from way back in 2018, with additional resources! I hope you find it handy.) Need a tool to parse message headers? Trying to break down how long it took to hand off an email message between servers? Want to check for blocklistings, conte…

Gmail's Sender Contact Form: What and why?

Did you know? Google has a " Sender Contact Form " for Gmail, previously known as the bulk sender contact form. What is it? It's a way for you to ask Google to reconsider their Gmail filtering decisions for your emails, to give them more information and contact i…

Microsoft SNDS: Common errors and how to handle them

Microsoft's SNDS (Smart Network Data Service) portal is a free and valuable deliverability resource for senders, providing direct data and feedback regarding your sending reputation. It also allows you to configure JMRP (Junk Mail Reporting Program), the Microsoft version o…

Seeing "recipient getting too much mail" delays at Gmail?

Here's a question I get asked from time to time: What does THIS Gmail SMTP delivery temp failure error actually mean? Here's the error in question: 450, "4.2.1", The user you are trying to contact is receiving mail at a rate that prevents additional messages f…

Gmail's Promotional tab: How to escape

How do I keep my email messages out of Gmail's Promotional tab? This is a common question lately. Is there one common answer? Ask six different people, and you'll get six different answers. And I'm not sure which answer is the best one, so I'll collect them here…