you really need to unlock via the SD card method.. its the best & works flawlessly for me EVERYTIME! screw rely'n on windows to unlock it or lets say your cat runs across your desk & unplugs ur phone while the RUU is going.. or lets say ( i know it never happens) windows crashes while you are flashing.. so many benefits to doing it the SD card method.
feel free to hit me up if you are lost in how to do it.
this thread is a huge helper to know how this process works. GL
Code
http://forum.ppcgeeks.com/showthread.php?t=61333