Those characters are "garbage" created by converting non-standard characters into standard characters.
The problem is next:
There are many diffrent operating systems, like: Windows, Mac, Unix, Linux, Lindows, Winux, ...
Then, on each operating system, there could be different language installed and different character set installed.
Then, to complicate the story, on each of those operating systems, you can have different browsers like IE, Netscape, Opera, FireFox, .... long list.
Now, on each one of those operating system you can create HTML document using local character set.
If you try to copy and paste that document, or part of that documnent by using a browser running on the different operating system and/or having different character set installed ... you may get different form of "garbage" characters.
If you try to edit that document, you may also get problems.
Blank spaces may get converted into "garbage" , ...
If you are editing a message taken from different operating system, try not to use those new HTML editors ... they may create garbage.
Also, try not to use different editors on the same message.
Like you create a message with FCK, but you edit it with MCE ... that may also create some grabage characters .....
Or, create a message with FCK on Mac machine, but you edit it with FCK on Windows machine ...
There are maany possible options, and without knowing what exactly you did, I can't
help ...
Rule of the thumb:
Avoid WYSIWYG editing, it may generate garbage!
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