PerfectIt 5 is compatible with Reference Checker. However, when you update Reference Checker, Word may disable PerfectIt. You can re-enable it by following the instructions for a missing icon in Word 2007/10/13/16/19 or Word 2000/XP/03. In this case, you won't usually need to restart the computer or re-install PerfectIt, so you can usually skip that part of the instructions.