Message bounced (Error 550 5.1.1) but received and opened

[Darren_Deliv]

Hi, 

I received the following bounce error message when sending to a contact 

smtp;550 5.1.1 MXIN501 mailbox ******@virginmedia.com unknown ;id=OO19kM2dqPvslOO19kMMH2;sid=OO19kM2dqPvsl;mta=mx5.tb;d=20201002;t=183447[CET];ipsrc=212.54.57.97;

The bounce was logged on 2020-10-02 17:34:47 however the email was opened 1 month later on 2020-11-07 20:56:36

I was wondering if someone could investigate and find why this is the case? 

Thanks, 

Darren

[ravenstar68]

It's a bit hard to diagnose what's going on without seeing the full bounce message - with email address redacted, and the full read receipt message

Tim