Use these Pre-install drivers:
ftp://driver.jmicron.com.tw/jmb36x/XP_Vista_Win7/ Extract the files and copy "floppy32" and "floppy64" to your memory stick and when its asks you to load drivers load the 32bit drivers first then the 64bit.
If those drivers dont work try the jmb38x drivers:
ftp://driver.jmicron.com.tw/jmb38x/XP_Vista_Win7/