Why is T-Mobile mail-to-SMS gateway sporadically blocking GMail?

James Britt wrote:

Philammon wrote:

I've been having the same problem here. I have our security cameras user the gateway to text images from the motion detection feature of BlueIris. Since about 4 days ago these texts have been sporadically rejected, but some get through after Gmail retires.  If it is a new spam filter it could be due to the pattern, so it may be worth trying to mix up the content.

 

It's not the pattern.  Same content, on different days or times, might get through, or might blocked,  it's all pretty arbitrary.   

GMail keeps re-sending a messages that get rejected (I think for up to 4 days).  So I will sometimes get a text on time, but most other times a text will show up hours later, or a day later, 2 days later.  Or never.

My guess is that the Amazon service (Cloudfront)  T-Mobile is using to control spam is poorly configured, uses multiple servers, and some of those servers block things for no real reason, while others let the messages through, 

It’s basically a crap shoot, and nobody at T-Mobile cares about this.

 

My messages eventually got completely blocked. The emails bounced back with the error "sender rejected". I made multiple calls to both Speint and T-Mobile about this. Most of the support people are clueless about this, but I finally got a tier 2 guy named Dan who knew what was going on. He created a ticket with CloudMark. CloudMark responded that "users" reported my email as a source of spam, which I know was BS because I created that email address to exclusively use email-to-text to *only* send messages to myself. And it wasn't hacked. They un-black-listed my email address and messages resumed. But they couldn't guarantee it wouldn't get blacklisted again. That was about 2 weeks worth of messages blocked. The thing that tells me that their implementation is poor is that a customer has no way to know if they never received a legitimate message (unless they were sending it to themselves). So I submitted a complaint to the FCC, whose new requirements implemented this year requiring providers to address spam started all this. I have no problem with fighting spam. It's the implementation that is the problem. Customers should have a spam box and the ability to whitelist senders.