Forum Discussion
Why is T-Mobile mail-to-SMS gateway sporadically blocking GMail?
I use the mail-to-SMS gateway to text me at different times of the day. For example, to alert me to do something on my to-do list, or to tell me if some long-running program on my PC, such as a backup, is completed.
Often the text comes through as expected. But, quite frequently, I get a message from GMail telling me that the email has been rejected , with a message similar to this:
421 4.1.0 <account@neurogami.com> sender rejected AUP#CDRBL
That email a via a custom domain that uses GMail to handle mail.
The curious thing is that this email (and a few others that are also custom domains with mail handled by GMail) is not really backlisted (as I think CDRBL suggests). Some messages from that account get through. In fact, Google will attempt re-delivery for quite some time if a message is rejected, and very often the mail does eventually get to me (albeit a day or two late).
My guess is that T-Mobile is rejecting messages relayed by one or another Google mail server, but not all of them. When a message is eventually resent via one of the servers T-Mobile seems to like, it gets though.
Meanwhile it sort of makes the mail-to-SMS gateway less than useful, as the idea of text messaging is that it’s fairly immediate.
You're still in the random delay phase. All my email-to-sms messages have been completely blocked for nearly 2 weeks now. And they were getting randomly delayed since April. I'm a Sprint customer, and this started before I even installed the T-Mobile SIM card on May 31st.
I do the same as you. My raspberry pi sends me messages from my automations.
I was just about to switch to Verizon because support has been less than helpful, but I decided to search for people on Verizon with the same problem… and they have it too!
My hunch is that it's spam filtering from a third party. T-mobile uses Cloudfilter and Verizon uses cloudmark. Both run on Amazon web services. I suspect it's triggered by a spam-like usage pattern or something. But I'm just guessing really.
My wife also recently reported that she’s not receiving picture messages a friend is sending her, but it's a group thread, so she can see that people are commenting on the pictures. I suspect it's the same root problem, but all I can do is guess since the support people are clueless.
