The following should get you taken care of -
1. Go to: Control Panel » Languages
2. Click on the "Language Editor" tab.
3. In the "Search String" field, type "UTF-8" and press "Go" button.
4. There may be one or two items that are shown. "myfeeds.php" and/or "generic.php" -- Click "Edit" next to "generic.php"
5. At the very top, you will see "CHARSET" highlighted in RED. Replace "UTF-8" with "ISO-8859-1" -- !!do not add any spaces or line-feed before/after this text!!
6. Scroll to the bottom and click on the "Update Language File" button. It does not matter which of the two buttons you click on, they both do the same thing.
Done.
Post a reply after you're done, to let us know how it goes for you.
NOTE: Its actually more simple than how the directions make look, I've just spread out each instruction to make it as basic as possible for anyone else who may stumble across this post.
