+++ This bug was initially created as a clone of Bug #615595 +++ This happens when you reply to a message encoded as UTF-16LE. The email metadata mentions characters as UTF-16LE, but it is actually encoded as UTF-8. So the message content has many chinese characters instead of its actual content. When encoding is selected as UTF-8 manually, it is shown correctly.

UTF-16LE should never be selectable as an outgoing encoding for e-mail. MIME can't handle those messages encoded in ascii-incompatible encodings.

That will be prevented in bug 1003716, but that's not on target for 31.

I am curious why this is labeled critical. Does this make Thunderbird unusuable?

Wayne, yes unless you expect users to be able to read chinese characters. I was unaware of the bug and I was scratching my head when all my friends asked me why I was sending them chinese email. The mail I replied to was sent by google drive when someone shared a document with me. So it is very likely to affect many people.

(In reply to Magnus Melin from comment #2) > That will be prevented in bug 1003716, but that's not on target for 31. This above bug is fixed in 36 and thus in https://www.mozilla.org/en-US/thunderbird/all-beta.html Praveen, Is it now resolved for you?

(Praveen seems to be gone)