MS365 Mail server destroy mail encoding

we upgraded RT4.4.4 to RT5.0.1 and send all mail from local through MS365 mail servers to our users and external recipients. We are located in germany and therefor use german umlauts in mail. Since we use MS365 server the mail encoding seems to brake and the german umlauts are not shown correct.

We have set:



Within the Webinterface everything looks fine.

I tested different mailserver and mailclients:

  • Gmail received mail through mailprovider ionos (not ms365)

  • internal HCL Domino Mailservers and Notes Client
    In this tests every mail looks correct, no broken signs.

  • Outlook Client: Mail is send from RT through ionos and received through ms365 to outlook: mail has broken german umlauts

What can I do to solve the problems with RT5.0.1 and mailservers from ms365?

Best regards,

I had a problem many years ago where messages forwarded to Request Tracker through Exchange were bouncing - not quite the same issue, and the bug in Exchange was later fixed. It was something to do with Exchange making mistakes with forwarding 8-bit MIME messages.

At the time, the workaround was to adjust our Postfix mail server configuration to set “smtp_never_send_ehlo = yes” which I believe forced Postfix to re-encode 8-bit MIME messages as 7-bit (due to falling back to the older SMTP protocol), avoiding triggering the Exchange bug by not sending Exchange anything in 8-bit form.

Maybe your problem is similarly to do with the cloud version of Exchange misbehaving when handling 8-bit MIME. It’s a bit of a long shot though.

I would suggest looking at the message sources if you can: look at the raw email sent from RT (in the ticket history) and compare that with what the same message’s raw source looks like in the Exchange mailbox. The changes between the two may point to what is breaking.

Or you could try changing EmailOutputEncoding to “UTF-7” if you think you can test that safely. I don’t know how likely that is to break anything though.

Hi Andrew,

thank you for your thoughts. I will look deeper into them.
I checked message sources sent from RT. There are all fine and encoded with utf-8.

Sources in Outlook look different. Some times I see a header with charset=us-ascii:
“Ticket URL:”
sometimes the header shows the expected charset=utf-8:

I think I try the option to set EmailOutputEncoding to UTF-7.

Regards, Torsten

Setting EmailOutputEncoding to UTF-7 solved the problem!
Thank You!

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