Since I installed Android Gingerbread everything was cool and fine. I was using Multiboot. Now one day I booted it and device don't want to neither boot neither show multiboot menu. All I see when booting is Noka logo. And then it should down I think.

So, I suspect I have to reflash my device (never did this before, when I had trouble I just re-installed last update with PC Suite and all problems was gone).

Today I tryed to reflash my N900 with this guide: http://wiki.maemo.org/Updating_the_firmware#Windows

I'm using Windows 7. I done everything, but then I got stucked at 7th step:

"Hold the u key on the device keyboard and connect the USB cable at the same time. See the Flasher documentation for more information. (TIP: Hold the u key until Windows has successfully installed the driver.) "

I do what it said keep holding U on my N900 keyboard, but driver wasn't succsefuly installed. I don't know what to do to fix this, since there is no way to boot up my N900.

Any ideas?

Windows 7 - 64 bit?
Then you have to workaround a problem with driver signing:
http://wiki.maemo.org/Updating_the_f..._Windows_7_x64

http://talk.maemo.org/showthread.php?p=1249962

win7 64 bit yeah