Okay, I see what you mean, I am getting the same message now.
Go here and follow these instructions,
http://pcsupport.about.com/od/fixtheproblem/ht/update-drivers-windows-7.htm
and see if maybe you missed any steps going through the device manager, if you get the same message still, or another error message, I can only conclude that there is a problem with file it's self, and you may have to contact AOC. To that end though, if you can select the native resolution that the monitor is suppose to work at, 1920x1080 @60hz, then you are okay, installing the driver will enable Windows to show the name of your monitor correctly, as well as only showing resolutions your monitor is capable of, but for all practical purposes, that is all it really does. The driver file actually does nothing that runs or effects the performance of the monitor.