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E-mail to SMS being blocked due to suspected SPAM


I work for a trucking company, and we use e-mail to SMS to send out dispatch messages to our drivers for load information. Drivers can then reply to those messages to have conversations with dispatchers who operate via e-mail.

This has been working for years; however, as of 3/26/2018, it seems our entire domain has been blocked by T-Mobile servers. E-mails sent to xxxxxxxxxx@tmomail.net are rejected with 550 errors. I have tried sending as plain text, e-mail, short, long, with picture, and just about every way I can think of, but it's always blocked. Messages sent to all other mobile carriers are still going through just fine.

I have tried calling support, but no lower-level techs seem to even understand what E-mail to SMS is, and they just exhaustively try things that are specific to one individual phone. They supposedly escalate the issue, but we never hear back. I am desperately searching for someone within T-Mobile who can actually tell me why my domain is suddenly being blocked. This functionality is critical for our drivers to do their jobs; I'd prefer my answer to those drivers not be "sorry, find another carrier" as they keep asking us why their messages are failing while all the non T-Mobile users are moving along just fine.

@srickar​ - I've seen where you've been super helpful to some people; is there any chance you could help us out, too? I can PM you specifics.

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Best answer by tmo_chris 5 November 2019, 00:21

Hello folks,

I wanted to pop in here and update the correct answer as the rules and guidelines on automated SMS traffic have changed.

  • Per Cellular Telecommunications and Internet Association (CTIA) Industry guidelines, Intercarrier guidelines and T-Mobile's own Terms and Conditions of Service, automated commercial SMS traffic routing on any network should use short codes.
  • Repetitive mass texts over 10-digit texting are forbidden by CTIA carriers, including T-Mobile. Continued SMS abuse can result in subscriber number being permanently blocked not only by T-Mobile, but also by other carriers, which is outside of T-Mobile control.
  • Commercial trafficking is only allowed through short code, and not through long code (10-digit numbers) and a customer must opt in to receive content.
  • Third-party services can send bulk messages, but such vendors are unaffiliated with T-Mobile.

This thread is now locked and will be archived 11/9/2019

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Hi @srickar,

 

I found this thread and wanted to add issue I recently ran into.  I'm using camelcamelcamel (amazon price tracker) to send email alerts to my gmail account.  I setup a gmail filter to forward these emails to my cell phone via the tmo email SMS gateway.

 

This worked fine for 1-2 weeks but then it stopped working and getting:

 

550 permanent failure for one or more recipients (XXXXXXXXXX@tmomail.net:blocked)

 

Emails are coming from noreply@camelcamelcamel.com

 

Also sending manual email from my gmail to tmomail is getting blocked too.  If I send from yahoo email it works fine.   Please help, thanks.

I am having a similar issue. I have my gmail account to forward emails of certain in stock items from 3 websites. Just received notification that the email account was blocked by tmomail.net

Userlevel 5

Hello folks,

I wanted to pop in here and update the correct answer as the rules and guidelines on automated SMS traffic have changed.

  • Per Cellular Telecommunications and Internet Association (CTIA) Industry guidelines, Intercarrier guidelines and T-Mobile's own Terms and Conditions of Service, automated commercial SMS traffic routing on any network should use short codes.
  • Repetitive mass texts over 10-digit texting are forbidden by CTIA carriers, including T-Mobile. Continued SMS abuse can result in subscriber number being permanently blocked not only by T-Mobile, but also by other carriers, which is outside of T-Mobile control.
  • Commercial trafficking is only allowed through short code, and not through long code (10-digit numbers) and a customer must opt in to receive content.
  • Third-party services can send bulk messages, but such vendors are unaffiliated with T-Mobile.

This thread is now locked and will be archived 11/9/2019

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Thanks for bringing that to my attention. I have resolved the issue with gmail.

Camel is a great tool for sure!

Hi @srickar,

I found this thread and wanted to add issue I recently ran into.  I'm using camelcamelcamel (amazon price tracker) to send email alerts to my gmail account.  I setup a gmail filter to forward these emails to my cell phone via the tmo email SMS gateway.

This worked fine for 1-2 weeks but then it stopped working and getting:

550 permanent failure for one or more recipients (XXXXXXXXXX@tmomail.net:blocked)

Emails are coming from noreply@camelcamelcamel.com

Also sending manual email from my gmail to tmomail is getting blocked too.  If I send from yahoo email it works fine.   Please help, thanks.

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Certain messages are failing because there is likely a few servers added that are missing configuration parameters such as system timestamp date and message-ID.. For example, one of the examples not sending over message-ID in the header, which is needed to prevent high spam scoring. Messages that are passing properly have all this included. Also, messages are sent in ALL CAPS, which increases score value.

A message ID looks something like this: Message-ID: <5dbc935e.jbOKy92mzMmaM9q/%@alarminfo.net>

Rule breakdown below

pts rule name description

---- ---------------------- --------------------------------

1.40 MISSING_DATE META: Missing Date: header

0.30 TVD_RCVD_SINGLE HEADER: 

0.14 MISSING_MID META: Missing Message-Id: header

0.00 NO_REAL_NAME HEADER: From: does not include a real name

0.01 SUBJ_ALL_CAPS META: Subject is all capitals

1.62 SUBJ_ALL_CAPS_2 META:

@srickar

We are also getting 550 errors when sending emails to the *@tmomail.net addresses. Not always, but quite a bit of our emails are getting bounced back. I sent you a follow request. the domain they are coming from is alarminfo.net

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.email TLD is okay to use. For example, https://gaggle.email/ is in use. It's the two character TLD international types that are likely blocked because of preponderance of spam from those sources. With ICANN's increase in available TLD choices, spam has increased and never know if a domain will be "memorable" enough for contacts and mistyped emails as most may default to .com, etc. Good luck in the transition.

Srickar,

My company is thinking about changing our FROM domain to one ending in “.email” as the domain suffix (top-level domain). Because that is the only other domain we have registered, and we need to shorten our FROM addresses for various reasons.

Do you think that “.email” will face SPAM problems with TMobile (and other recipients)?

@srickar

Not sure if you did anything but everything now works with forwarded emails to SMS from slickdeals.net. Thank you.

I think I sent the inbox follow request, but I don’t see a way to send you additional informantlion.

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No sorry, cannot whitelist external entries. The reason certain messages are blocking is due to sending out survey links for .us TLD. This is a common spamming tactica which these messages are similar. This type of solicitation ideally should be routing over a subscription shortcode based service as these emails are sending out solicitation asking recipients to click links.

@srickar​ my team wanted to know if it were possible to add a particular whitelist our carehere.us domain for the survey or sending email address that flag our email? 

@srickar​   How can I get a message to you - I have the same issue?

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Send me an inbox follow request and I can investigate more closely. Thanks.

Hi @srickar​, I changed it so my email account forwards the email directly to my phone via text message (instead of forwarding the email to another email account that then forwards the email to my phone via text message).

I'm getting this message now:

"Message blocked.  Your message to [my number here]@tmomail.net has been blocked. See technical details below for more information. 

The response from the remote server was:  550 permanent failure for one or more recipients ( [my number here]@tmomail.net:554 rejecting banned content)"

Is there something else I need to do?

Thanks!

Try using something besides info@ourdomain.com<mailto:info@ourdomain.com>. Info, Webmaster, Postmaster are blocked because of spam.

I am having the same issue - can you assist? I sent a message - maybe I am not doing this correctly - but I sent this message -

Hello! We are having the same issue and could use some help with this. I was able to receive email to SMS on my tmobile device until just recently. I was testing a new service we intend to provide to our customers as we have an online auction site and customers would like to sign up for a outbid notification. Please note that they have to sign up for this service. We can send to ATT and Verizon and other carriers but get this bounce back from Tmobile.

The email is coming from an info@ourdomain.com

XXXXXXXXXX@tmomail.net

    host d79033b.ess.barracudanetworks.com [209.222.82.126]

    SMTP error from remote mail server after end of data:

    550 permanent failure for one or more recipients (XXXXXXXXXX@tmomail.net:554 rejecting banned content
We will try changing the from / sender email and see if that helps - if not what do we need to do to get our domain white listed?

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Hi @hiddensoundhostel

That issue is quite different from other examples. In this case, double relay forwarding is not permitted because proxy forwarding of spam also utilizes this method. The purpose of double forwarding allows for spamming entities to circumvent direct detection using webmail providers that cannot be outright blocked. If sent directly, the messages will pass.

Hi @srickar,  I'm having the same issue as everyone else.  I sent you a follow request.

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Greg,

Id like to look into this further. I could not locate a sending domain to the # listed in the ticket. Can you please follow me back through inbox and send me a direct message? Thanks.

Hi,

I am having the same problem.  We are an alarm company where our alarm panels send out email-to-SMS messages to our customers.  T-Mobile is now blocking 550 our emails.  We need to get our domain white listed as well.  I opened a support ticket, # 25596751, today by phone, but they really didn't seem to understand my problem.  I'm really hoping to get white listed as our customers with T-Mobile can't receive any alarm notifications right now.  All other carriers receive the messages without any problem.

-Greg

Hi srickar,

I have the same problem as everyone else. I have emails of shopping deals from a website (slickdeals.net) that gets sent to my gmail. I have a gmail rule that forwards these emails as SMS messages to me at xxxxxxxxxx@tmomail.net. But recently, the messages have not been getting sent to my phone and I get an error email from Gmail, pasted below. Any help is much appreciated. Thanks.

Message blocked

Your message to xxxxxxxxxx@tmomail.net has been blocked. See technical details below for more information.

The response from the remote server was:

550 permanent failure for one or more recipients (xxxxxxxxxx@tmomail.net:554 rejecting banned content)

Hello! We are having the same issue and could use some help with this. I was able to receive email to SMS on my tmobile device until just recently. I was testing a new service we intend to provide to our customers as we have an online auction site and customers would like to sign up for a outbid notification. Please note that they have to sign up for this service. We can send to ATT and Verizon and other carriers but get this bounce back from Tmobile.

The email is coming from an info@ourdomain.com

XXXXXXXXXX@tmomail.net

    host d79033b.ess.barracudanetworks.com [209.222.82.126]

    SMTP error from remote mail server after end of data:

    550 permanent failure for one or more recipients (XXXXXXXXXX@tmomail.net:554 rejecting banned content
We will try changing the from / sender email and see if that helps - if not what do we need to do to get our domain white listed?

Thanks, @srickar.  Is there any way that we could have a particular address whitelisted so that texts with URLs are not flagged?

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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 support@customerservice.com, when the domain is actually is support@gmail.com. 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."

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