421 4.2.0 sender rejected AUP#SNDR

Finally talked to an engineer (Dan) that is familiar with the spam filtering they do. (I thought I commented this before here, but I don’t see it, so... I learned that the domain sending the “sender rejected” error [cloudfilter.net] is owned by markmonitor.com, which is the company that must have been contracted out by T-Mobile to do spam filtering.)

Dan said that he was already familiar with this issue because he is handling the same exact issue for another customer. And apparently he doesn’t have the capability of solving the issue directly. He created a ticket for the appropriate team to try and resolve the issue and said he would call me back.

I have 2 gmail accounts (one for my home automations that is blocked by markmonitor and one that I use as my primary email). I noted that if I send emails from my primary account, *sometimes* those messages get through and sometimes they’re blocked. The other account however hasn’t gotten a message through since 2 weeks ago and I checked that account for “sender rejected” error bouncebacks. I have 142 such bounceback errors. That’s about 10-12 messages per day on average over the past 13 days (though I don’t know if any of those bouncebacks are repeated - I don’t think so - each one is maybe the 3rd bounce-backs in a series of temporary delays that ends in the “sender rejected” error).

Dan said that it could take 24 hours for the spam team to address my issue. I guess we’ll find out...

I learned via an SMS service called RingCentral that the spam filtering that was blocking my legitimate messages is due to new FCC rules about mobile carriers and spam filtering.

So I just submitted an FCC complaint at: https://consumercomplaints.fcc.gov/hc/en-us/requests/new?ticket_form_id=39744

that addresses what I believe to be an unintended side-effect: blocking of legitimate messages with little recourse for consumers. I suggest others facing these same issues should also submit their own complaints. Otherwise, we’re subject to arbitrary blocking of our own sent messages and messages we want to receive.

Here’s the content:

I have a series of home automations that use my mobile carrier's email-to-text feature to notify me when something notable happens in my home. These messages can include a security camera alert, motion alerts, moisture alarms, smoke detector alerts, etc., among other mundane messages. The average number of messages I receive per day using that feature is roughly 10 messages and I do not use it to send messages to anyone else. I set up an email account on gmail to be used exclusively for this purpose. I have used this method of messaging for years without issue until April/May of 2022.

On Tuesday July 19th, my home automation messages completely stopped. It took me many calls to tech support at both Sprint (my original carrier) and T-Mobile before the block on my email account was lifted. It took 2 weeks to resolve and they told me there are no guarantees it wouldn't get blocked again.

In talking with the last tech support guy who was able to identify and (temporarily) resolve the problem, I learned a few things:

1. T-Mobile contracts with a third party (a company called CloudMark) to perform spam filtering.
2. There is no way for a customer to directly request to CloudMark that a block on an email address to be lifted.
3. Tech support personnel are largely unaware of the spam filtering in use (which is why it took so many separate interactions and 2 weeks to resolve my issue).
4. Recipients have no way of knowing if a legitimate message sent to them has been spam filtered. (There's no way to for example, check a spam folder.)
5. The random message delivery delays (which can be in excess of 24 hours) are due to the spam filtering mechanism. This causes messages to arrive in a non-chronological order and can delay messages where timeliness is critical (e.g. my basement is flooding).

I have thoroughly researched this issue over the past 2 weeks and when considering whether or not to change carriers, I discovered that this is an issue with other carriers as well (e.g., Verizon) and is a fairly recent issue. I have interacted with a number of other people in forums who experienced the same problems as me.

I think users should have the right to whitelist messages sent to themselves or the senders as "not spam", because this spam filtering is blocking legitimate messages. Users should have the right to request compensation for failure to deliver messages. Users should also have the right to opt out of spam filtering for messages sent to them. There needs to be transparency all-around. Spam should be handled the same way as email providers do: create a spam box and give users controls to fine-tune their spam filtering.

At the very least, if the usage of email-to-text features are allowed to be limited by carriers or messages filtered without customers' knowledge or consent, users should be informed as to those limitations, such as number of recipients and/or messages allowed within a time window, the delays they can expect to experience in delivery, and what indicators are used to block either their own outgoing messages or messages sent to them. I tried to look up and requested those guidelines from T-Mobile and they had no information to offer that would enable me to avoid getting my email account blocked.

Furthermore, there should be honesty. The tech support person I spoke with claimed that Cloudmark said that other users identified my email account as a source of spam, despite the fact that I have NEVER sent a message from that account to anyone other than myself and there is zero evidence my account was hacked or that I have any other recipients in my sent mailbox other than myself.

And under the additional info, I entered:

This isn't about receiving an unwanted text - it's about not receiving a wanted text, but the categories provided don't account for this circumstance - please update your form to address mobile carriers blocking legitimate messages under the guise of spam filtering.

I would love to see that apple script @hepcat72 . My Email to Text has been delayed/broken for weeks. Pretty much the exact issues described in this thread.

Thank you so much for this info.  It is extremely frustrating.  I completely agree with having a “spam” folder for the texts they are blocking.  We utilize a 3rd party app at work.  Which has 2 factor authentication set up.  This means the cell companies know the texts are coming from a legitimate site.   We would text are technicians info in the field directly from our software.  These guys are electricians who don’t have computers readily available when they are at a customers home.  Not having this feature is really causing issues.  What it comes down to is all the carriers want people to pay for sending texts like these.  It doesn’t matter that we as a company pay our cell phone bill and the recipient of these texts pay their own bill...they want to bill us on top of that.  Absolutely ridiculous.  Why when I am driving down the road and I pass a Kohls, I will receive a text about some coupon they are currently offering but if I sent a text from an authenticated app it doesn't go through????