USB drive problem

[vash_6800]

I'm using boot maker to prepare an USB pen for flashing. I've done the flashing with the exact same pen before, but this time i got an error message:

Windows - Drive not ready
The drive is not ready for use; its door may be open. Please check drive and make sure that a disk is inserted and that the drive door is closed.
<cancel><try again><continue>

If i press either it just shows up again a half second later.

What is the problem?
Thank you for any comments!

 

[zerach]

i would start using iprep.xbm is not supported any more

try it in a different usb slot
make sure the usb drivers are good

 

[vash_6800]

tried iprep and different usb slots, but got the same message. got a pretty expensive 4gb usb pen too. However! if i just press continue the message returns but the iprep process completes as well =S says its ready for use. Im trying to flash with it now, hope it works. Thanks for your help