I guess it shouldn't be a problem to use command prompt in Win7. Run the flasher program and plug-in n900. If its recognised then the flashing will proceed or otherwise it will wait till n900 is connected.

On Debian, i'm able to lsusb (list usb devices) to see if n900 is connected or not.

Most of the time with IT, we just have to try and error with different combination till it work and share our experience. Good luck.

Wilson