We are getting a similar issue with our employees/your customers. Is there anything my company can do?
srickar, I am having the same problem. WE were successfully sending emails (domain authenticated) yesterday from our field services devices to TMobile numbers. This morning, they seemed to be blocked. What can we do?
From our email provider SendGrid:
Received by d79033b.ess.barracudanetworks.com
2019/10/23 10:17am UTC-04:00
The tmomail.net server blocked this message from being delivered. While we won't try to send this message again, we will attempt to send new messages to this address in the future.
You can view all addresses in your Blocks suppression group. Learn more.
Full response from the tmomail.net server:
550 permanent failure for one or more recipients (email@example.com:blocked)
@srickar, let me know if you need the sending domain, or the phone numbers that were sent to.
Thank you @srickar for your reply.
We generate appointment confirmations to clients a day before their
appointment. Our email address is firstname.lastname@example.org. Here is
the response I am getting when emailing to a T-Mobile client:
This message was created automatically by mail delivery software. A
message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:
email@example.com SMTP error from remote mail server after end of
data: host d79033b.ess.barracudanetworks.com : 550
permanent failure for one or more recipients (firstname.lastname@example.org:554
rejecting banned content)
If possible, please edit/remove identifying information in your cut and paste.
The appointment reminders are passing just messages that discuss Facebook. I checked, and the reason why this is blocking is a facebook URL is pasted in the message body. This type of block is necessary because spammers are sending out similar facebook spam containing adult content. If you could please remove the facebook footer from messages they will also start passing.
Thank you, srickar! That did the trick.
Hellosrickar I seem to be having the same problem as others. It seems like it started Friday evening, and I've checked that we are passing SPF, DMARC and DKIM checks in the headers. It's only happening with tmomail.net and mymetropcs.com (which I believe is an MVNO through you guys) no problems through att, verizon, sprint etc.
10/22/2019 3:19:54 PM
550 5.7.350 Remote server returned message detected as spam -> 550 permanent failure for one or more recipients (XXXXXXXXXX@tmomail.net:554 rejecting banned content)
DSN generated by:
Any help you can give is greatly appreciated.
Did you check today? They are passing as I had made some changes yesterday 10/22 around 1230pm CDT. Please note that email could be blocked again due to matching with spam activity that's ongoing.
Reason was due to spam storm that's also using info@. It would be best to avoid using generic usernames that match with spam activity. Examples would be info@, postmaster@, admin@, test@, etc which are too generic but used by spammers which will cause your traffic to get lumped into same category. Unfortunately, spam attacks are heavy right now and can result in false positive blocking. Thanks for your understanding.
Just informing everyone that I will be out of office October 24th and 25th and will have limited ability to answer messages. I shall return on Monday Oct. 28th. And of course you may always contact T-Mobile TEXperts at 611 and submit a ticket for @tmomail.net if you are experiencing issues with email delivery. Thanks.
Hi @srickar. On our Inbox back and forth, you quickly unblocked Mindspring, and I think you took off. I wrote back quickly we were using SendGrid. When you get this, can you check back with us (even if it is next week at this point).
I have a similar situation but its a bit different. We use an smtp Client to connect to a gmail account that sends the email.
For some reason the manual email doesn't get blocked but the email through the smtp client does.
I tried this from another smtp client on another pc as well and was still getting blocked.
Can you tell me what exactly is the banned content? If anyone else has any ideas please let me know.
I black out some parts for privacy concerns but I can dm you the full details.
I found the message based on the power of * search.
You have an empty "Envelope From:" field which is a requirement for SMTP acceptance.
Please configure the sending server to have this and it will pass.
One more item to note, you have an email address with test@. That is currently not allowed because of the generic nature due to a spam storm right now posing as officially titled user names. (test@, admin@, webmaster@, postmaster@, administrator@, etc).
Thanks srickar. I believe it worked. I just used test2 instead of test .
For anyone else wondering your sender has to be the same as the true sending address. email to tmomail.net rejected for banned content
"IMPACT: Customers may be unable to receive messages to messages to their MSISDN@tmomail.net address. To help aid the attack against SPAM, T-Mobile is now blocking traffic where the sending Domain is altered from the true sending address: IE email@example.com, when the domain is actually is firstname.lastname@example.org. senders will receive a 550 bounceback error . To correct this issue, Senders will need to revert their sending address to their actual email address. For assistance, direct customers to the sending party, and sending parties to their domain customer support. this service is functioning properly."