Office 365 – Emails sent to Office 365 group contain Chinese characters

Recently I've noticed that when I send email to Office 365 group from my iPhone (iOS) standard Mail application and people respond to it they get Chinese characters in them. This is visible in place of:

—–Original Message—–

From: Przemysław Kłys

Sent: Tuesday, June 27, 2017 9:01 AM

To: <office365@group.pl>

Subject: <standard topic>

After further testing the issue seems to be related to all emails sent to Office 365 groups as plain text. Not only to iOS emails.

In standard email when people respond it usually contains information with fields like From, Sent, To and Subject.

However what I've noticed is that if email is sent as Plain Text it's actually totally scrambled as below using Chinese characters

In text it looks something like this which is very weird

䐼噉氠湡㵧汰挠慬獳伽瑵潬歯敍獳条䡥慥敤⁲污杩㵮氢晥≴䐠剉∽呌≒‾䘼乏⁔慆散∽≃匠穩㵥㸲㰭剂‾䈼䘾⼼㹂倠†䈼㹒㰠㹂㱓䈯‾㱔剂‾䈼吾⼼㹂䄠䈼㹒†䈼匾⼼㹂䄠䈼㹒†㰠䘯乏㹔㰠䐯噉㰾䥄㹖⼼䥄㹖

This only happens when the message is sent to a an Office 365 group, and only if sent as plain text. It doesn't appear on RTF or HTML formatted messages. When I've checked what that actually means there was no direct translation from Chinese to English

For Chinese to Polish it gives a bit different meaning but it totally makes no sense so I guess it's just bug on translation.

At one point when I checked the translation the text claimed to be more like Viagra selling solutions. Fortunately it seems that the translation from Chinese to Polish/English is just not good enough. To be honest I am assuming those are Chinese characters because I actually can't read them. Those can be totally made up signs as far as I know.