Recently I’ve been receiving email in Mozilla Thunderbird which display odd characters. Changing the character encoding of the individual message solved the problem but only for that message.

Auto detection of the character encoding was enabled but didn’t seem to be working – until I messed around with the settings and did this:

  • Go to Tools > Options > Advanced > Config Editor and make sure that mailnews.force_charset_override is set to false
  • Now right click on your Inbox and choose Edit > Folder Properties and make sure that the checkbox “Apply default to all messages in the folder…” is NOT checked.
Use the Config Editor to ensure that mailnews.force_charset_override is false (its default setting). Also choose Edit – Folder Properties… and ensure that the checkbox “Apply default…” is clear.