This error message just started today out of the blue. It started reading Unable to load the Parallels driver Restart your Mac and try again I have tried many times and tried re installing but nothing seems to work...
Hello AlistairB! Check this thread with similar "restart your mac" error: http://forum.parallels.com/showthread.php?t=112047&page=2 Please let me know if it'll help you! Also I think it's better to post this type of messages to http://forum.parallels.com/forumdisplay.php?f=59