joaopbnogueira

Or having a lower % of body fat (within healthy limits) is the factor improving a better immune response?

The issue was eventually solved by - creating a Microsoft account and subscribing to 365 - opening a support ticket - systematically escalating the issue with evidence of what was happening (message traces, example emails, etc) - pointing to evidence on other blogs/sites that discussed the same problems

Thank you all for the suggestions.

Thank you, you've gotten further than I have.

On my "quarantine" I can't find anything (it's empty) therefore I can't also check what's going on. But "URL detonation reputation" is consistent with the behavior we're observing.

Ok, that was smart. I bet it was fixed quickly.

This sounds like what's happening to us, but only if the dreaded 25friday.com keyword is included on the email content

We thought about it but: - this a statically generated site (SSG using Next.js), so there's backend runtime for the FE itself. - we do have a contact form, but under the hood it sends an email to our own inbox through internal APIs and the destination email is hard-coded, so I don't think they could hijack this (will check the audit log just in case). - it's hosted using Cloudflare pages - the worker/api part is severely rate limited - we would notice abuse since we have low monthly email sending limits on this api service

Ah, but we have purchased 1 license of MS365 precisely to help triage this issue and open a support ticket but the agent is as clueless as we are....

I'm with you but it's very hard to change the tools our clients use :)

We also had a look at it, but the problem is that we don't control our mail server as it's Google provided.

Could be the reason, but even so, we have really low volume campaigns and mostly to people we actually interact / have a history with. I would assume it would take more than a few accidental hits to trigger this issue.

Well, it works fine for every single recipient unless it's a Microsoft one.

If the recipient is using a personal microsoft / outlook / hotmail account the email gets delivered with a spam score of 9.

If the recipient is a MS 365 account, blackhole it is.

We even set up our own MS 365 to prove this.

I guess only basic since our main provider is Google, not MS.

We do use Azure for small stuff, but too small for any special support channel.

I'd love to but what see in practice is that the bigger the company the more likely it is that they use MS. Which hits double hard since this means our bigger clients are the ones not getting our emails...

Joking aside, we are seriously considering moving all comms to 25friday.nl (which we also own) if we can't find a way around this...