We've had a problem with this and it only happens to some members, not all.
I'm trying to nail down the problem and need more information to do this.
NOTE: If you are not having this problem with your posts please do not respond to this thread. I'm only after information from people who do have this problem. Furthermore, I'm only concerned about when it happens to posts you make from scratch. Obviously quoting someone else's post is irrelevant.
If you are having this problem I'd like to know:
1/ Are you using a program like Word to compose your posts and then copy/pasting them into the forum reply window?
2/ Have you set your browser to fixed UTF-8?
ETA: Note that if you are using a Microsoft editor like Word to compose your posts it will make a mess of apostrophes due to Microsoft's coders being idiots, as usual. http://www.simplemachines.org/community/index.php?topic=282676.msg1858242#msg1858242Another path to pursue: when people type in apostrophes and quotation marks, and they're changed to oddball/unprintable characters, it's the result of using a Microsoft editor. The "editor" (such as Word) "helpfully" changes the quotation marks and apostrophes to the typographically correct glyphs. This is called "smart quotes". Unfortunately, the character set that MS uses is not a standard one, and thus quotation marks and apostrophes don't show up correctly on a Web page. They're in an area reserved for control characters.
Also:
http://www.simplemachines.org/community/index.php?topic=282676.msg1873587#msg1873587What are you producing the original text in, before cutting and pasting it into SMF? If you're using Word (or similar Microsoft word processors), you will have to find a way to turn off the "smart quotes" function. It turns your apostrophes into typographically correct glyphs, but unfortunately, MS used nonstandard code points for these characters.
Now people, I've done some testing and have discovered something. Open Office does not make a mess of apostrophes. If you use Open Office to compose articles then you can copy/paste them without any problems. It's free and open source software so it's worth thinking about. I have it installed myself, of course.
Open Office.org