If you see a little box with hex code then that means that Unicode is used on that page.
The range 0x80-0x9f isn't a valid Unicode range.

• http://en.wikibooks.org/wiki/Unicode/Character_reference/0000-0FFF

You need to check the encoding in View > Character Encoding and change it to a Windows encoding like Windows-1252 (ANSI).
You can also try View > Character Encoding > Auto-Detect : Universal , but that can cause the wrong encoding to get selected.
The setting in Tools > Options is to set the default if a website doesn't specify an encoding.

Thanks for your help. I've set Western - Windows-1252 in both View and Tools.

Now I just have to wait until I get those newsletters again to be sure I did it right.

You're welcome

It is best to leave the default encoding as set in Tools > Options to the default Western (ISO-8859-1) and use the View > Character Encoding menu to select another encoding in case of display problems on web pages.

See also:

• Content Preferences: https://addons.mozilla.org/firefox/addon/content-preferences/

I reset the View - Character Encoding to Western - Windows 1252 as you suggested and got an email that still displays the box with 0 0 92 in it. So I changed the encoding to ISO-8859-1 and then to unicode -- all with no effect.

I think I don't understand how this is supposed to work, or how and when I'm supposed to change the View-encoding.

Sorry to be so dense.

You need another Windows encoding (e.g. Windows-1252) to get rid of that 0092 box, Unicode and ISO-8859-1 won't display that character.

Did you try the View > Character Encoding > Auto-Detect : Universal choice to see which encoding gets selected?

I'm still getting the 0092, even after I changed the View-Character encoding to Windows-1252. It doesn't matter if I do it before or after I open the email. I even got out of the email system and set it to Windows-1252-then opened email. Still get 0092.

When I have the email up with the 0092 and look at Character encoding, it shows Windows-1252.

Is there a specific order or time when I must set the Character encoding? Do I have to get out of Firefox and then restart it?

You need to make changes in View > Character Encoding while you have that specific page open in the tab that is currently selected. It only applies to the current tab.

I've done it that way and still get the codes.

The character encoding shows Windows-1252, but still the codes.

I think I'll give up on this. I'm sorry I've taken up so much of your time. Thanks very much for trying to help me.