Showing posts with the label blocking

Gmail: New spam-related rejections and what you need to know

Gmail has very recently unveiled a series of new deferral/rejection messages. You may want to familiarize yourself with the following new SMTP responses: 421 4.7.28 Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our user…

Stuck in the middle with you: When shared domains are actively risky

What do you do when you're a newsletter publisher or marketing manager sending emails to your list and you run into deliverability trouble through no fault of your own? How do you even know? It's a tricky and sticky situation and I've seen it happen more than once l…

Chrome turns on real-time phishing protection

Michael Crider (staff writer for PCWorld) is one of the many folks reporting on Google's new real-time anti-phishing protection in the Chrome web browser . This means checking every domain you're trying to visit against some sort of domain or URL blocking list. Aside fr…

Microsoft: Blocking Email from Persistently Vulnerable Exchange Servers

Microsoft recently posted that their Exchange Online servers (which I think also includes Microsoft 365/Office 365, basically any business email cloud-hosted by Microsoft) will soon block mail from old, unpatched Microsoft Exchange servers . Unlike the recent DMARC changes for …

Blocked at t-online.de?

On Tuesday, June 9th, 2020, various mail server administrators were reporting that they were now having trouble delivering email messages to large German ISP and mailbox provider (and telecommunications company) T-Online. In various tests, many people who connect to port 25 of …

Ask Al: Help! How best to send to 70 friends at once?

Thierry writes: "For the past 3 days I have been identified by Spamhaus as a spammer, I guess, as I get error 554 when sending to domains that they filter. As you can see I have a mail.com address. "The only change in my recent email activity is that for the past 10…

Ask Al: Group mail is being blocked, what do I do?

Recently, a reader wrote in with the following question: I host an email group of about 450 people who share a common autoimmune medical condition. I send/receive email through a Gmail account set up in Windows Live Mail on a home PC. My ISP is RCN.  Recently, any emails sent…

Help! I'm blocked at Verizon.net! (Updated for 2024)

Hey! Are you finding your mail rejected when trying to send to verizon.net? Through a complicated series of mergers and acquisitions over the years, AOL and Yahoo and Verizon have all merged into a single MBP (mailbox provider). The surviving entity? Yahoo! Mail. Thus, if you&#…

Ask Al: Help, I'm blocked at AT&T!

Jay writes: Al, I am getting the following message on several email related to AT&T: flph260 DNSBL:ATTRBL 521< xxx.xxx.xxx.xxx>_is_blocked.__For_information_see_http://att.net/blocks After going the ATT site, using Spamhaus to check the IP as well as using AT&T…