I recently saw this happening in my own outgoing email, and I think it's because I had re-set the fonts to clean up the mess made by the message having been replied and forwarded by several people.

I'd reset it to Arial which is not utf-8/unicode compatible. I have since switched to Lucida Sans Unicode, which is utf-8 compliant.

Are your messages broken when you send them, or only after they arrive? In the second case, it may be the recipient's email client breaking them, and it may be wise for you to be less ambitious and use one of the Windows encodings.

Oh, and I'd suggest you also check your settings for "Other writing systems", as an alternative to where you have "Latin" at the top.

I fear your choice of Arial may be part of your problem.

Good day Zenos, Thank you for prompt response. The problem is peculiar- I am having the problem in my office computers. We have 8 PCs with Windows 7 installed, same config, same settings. Out of 8, only 4 PCs are having this problem of � � � � � characters in emails received by recipients. All PCs have same version of Thunderbird installed - 52.6.0 (32-bit). Wierd, is'nt it?. I have done as per your suggestion. However problem still persist. Attaching all snapshots in one file for your review.

in every case I have seen the emails in question specify the use of non unicode font. In every case it has been Arial that was specified. But what is not clear in this thread is the change only impact new email. Old emails specifying arial will still show the poor formatting

I have the same problem, � appears freequently ... almost as if at every spacebar hit. Not in every email, however, and I have not been selecting one font or another, now or ever. This does seem to have begun a month or two ago, I didn't notice it until a recipient commented. So, the above re Arial does not seem quite right, since whatever font Tbird selects is what I use ... and have been for several years. This is a new problem, and seems to be caused by Thunderbird, starting several weeks ago. What's caused it, why is it only on some emails, and how can Tbird correct the problem it seems to have created? Here is an example of what was received today, from an email sent today: �Just to let you know that the book,�"Understanding Women",��is finally available in paperback.� And I understand Volume 2 will be out next year. �� ��

Here is what is in my Sent file: Just to let you know that the book, "Understanding Women", is finally available in paperback. And I understand Volume 2 will be out next year.

@Rightcoaster It is a problem alright. When it is not the font it is the idiot in charge of a mail server that thinks Unicode is for other folks. Yahoo tried it for a while. Perhaps it was their US centric view of the world were everyone speaks unaccented English. There was a provider in Germany that thought it would be a good idea is they did something to ignore Unicode as well.

So I suggest you actually ask your own question instead of piggybacking on someone elses. I know it will be a first. But it is how things are supposed to be done.

I suggest you make your question complete, including the domain you are mailing from and the domain your are mailing to if it is only some folks.

Thanks for the suggestion to post a new Q ... but when I went to take you up on it, I came across this: https://support.mozilla.org/en-US/questions/1193450#answer-1046665, and decided to try the display change settings/Set Unicode, etc., approach first. Sent test messages to a couple of friends who'd gotten the � treatment, will await responses and see. Maybe Mozilla might send around or post a notice somewhere easier to find than this exercise has been?