So, after installing my font library, while trying to scroll through my fonts to preview some text, I noticed cs4 kept freezing on certain fonts. ISSUE While you use the arrow keys on the keyboard to scroll through the fonts list in the Character menu (under Window menu > Type) will freeze on certain fonts in Adobe Illustrator CS4. SOLUTION Turn off Enable Missing Glyph Protection. InIllustrator CS4 choose Edit > Preferences > Type. Remove the check-mark for Enable Missing Glyph Protection. ---- Turns out the @ sign did not agree with some fonts. Very annoying. Took about 30 minutes of google to find that solution so just in case anyone else runs into it maybe you read this first.