T-Online blacklisted SES IP addresses

Question

Hello,  
  
Since December 2019 T-Online blocks again AWS SES servers.  
Following bounces appear everytime my app sends a mail to T-online mailboxes with SES:  
**smtp; 554 IP=54.240.48.131 - A problem occurred. (Ask your postmaster for help or to contact tosa@rx.t-online.de to clarify.) (BL)**  
  
There were similar threads in the forum:  
https://forums.aws.amazon.com/thread.jspa?messageID=695663&#695663;  
https://forums.aws.amazon.com/thread.jspa?messageID=703368&#703368;  
  
Could you please urgently help to resolve this?  
Thank you!  
Heinz

Answer

Dear AWS SES Team,  
  
We are having the exact same issue. Could you provide some help in this regard?  
  
Best regards,  
Lionel

Answer

Hi Heinz,  
  
I checked with our engineers, and I can confirm that Amazon SES delivered messages to t-online.de inboxes on the dates in question.  
  
I sent a private message with some tips that might help improve delivery of your messages. Please let me know if I can provide any additional assistance.  
  
Thank you,  
  
Brent

Answer

Hello Brent,  
  
Here are two message-IDs (from the bounce):  
0100016fdc0dbd40-48326b36-1a70-4008-9949-a7645db02f51-000000  
0100016fdc0d16cb-6ffa80c3-ab6a-4777-86ff-f019eddcf067-000000  
  
Thanks, Heinz

Answer

Hi Heinz,  
  
Do you have the SES message ID of an email that produced this result?   
  
Thank you,  
  
Brent @ AWS

Answer

Dear all,  
  
We have the very same problem. Any help would be much appreciated.  
  
Best regards

T-Online blacklisted SES IP addresses

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