Inline images in outbound email

Inline images seem to be stripped out of outbound emails sent by RT in my setup. When I receive an HTML email with inline images, it shows correctly in the RT web interface, but the email sent to AdminCcs etc has the image tag stripped out of the HTML. The image is still attached however.

If the owner replies to the requestor via email with an image, it is also stripped out.

Further the emails stripped this way seem to contain an HTML section all in

 and they’re in multipart/mixed which Thunderbird displays quite strangely (plain text, then HTML, then the images).

I see some traffic about this from over 3 years ago regarding RT 4.2.5 with patches in the RT tracker; is this still the only solution? I have 4.4.1.


I applied the patch to, but it didn’t help. Do I also need the change to mentioned in that other discussion? The RT 4.4 code looks quite different to the context shown in that old email (

I have the same problem. Until now I’ve used plain text correspondence so I didn’t notice this before.

I’m using RT4 (4.4.1) in Debian 9 (stretch). Don’t know if this matters but this system was initially installed in Debian 7 and then upgraded to the present state.

My Correspondence in HTML template is:

RT-Attach-Message: yes
Content-Type: text/html

{$Transaction->Content(Type => "text/html");}

The email message structure the users are getting is:


The html part 1.2 inside the MULTIPART/ALTERNATIVE is simply the plain text message wrapped around a <pre> tag. Part 2 is the proper html message, with images with CID source. However the part displayed both in thunderbird and gmail is part 1. The end result is that the users are not able to see the images inline.

I’ve also applied the patches mentioned here, (affected files: and MessageBox). No success.

Any help is appreciated!

Thank you.

Small update:

I’ve noticed that if I send the message from gmail everything works as expected. If I create a similar message from thunderbird we have the problem I’ve described.

The messages sent from gmail and thunderbird do have different structures, don’t know if this is enough create this situation but in the web interface the messages received from both clients work as expected.