works on windows 7

Download the Flasher for your device model: N900
http://wiki.maemo.org/Documentation/...mo_Flasher-3.5



Flashing using the command line
In order to flash directly from the XP/Vista/Windows 7 command line, follow these steps:

1.Download and install the latest version of Flasher e.g. maemo_flasher-3.5_2.5.2.2.exe
2.Download the latest firmware (.bin) file and save it to %ProgramFiles%\maemo\flasher-3.5\ (the default installation path for Flasher) or to the custom path of your choice.
http://tablets-dev.nokia.com/nokia_N900.php


3.Ensure the battery is at least half full.
4.Unplug charger cable and switch off the device.
5.Open the Command Prompt (Start then Run or Windows Logo key + R) and type cmd then press Enter.
6.Change the directory to the Flasher's path (TIP: Use the TAB key to auto-complete the commands and file-names)
cd "%ProgramFiles%\maemo\flasher-3.5" 1.Hold the u key on the device keyboard and connect the USB cable at the same time (see the Flasher documentation)
2.Run the following command:
flasher-3.5.exe -F RX-51_2009SE_2.2009.51-1_PR_COMBINED_MR0_ARM.bin -f -RReplace RX-51_2009SE_2.2009.51-1_PR_COMBINED_MR0_ARM.bin with the firmware you wish to update (The name of the firmware image file you downloaded in the beginning).

The update will take approximately 4 minutes after which the N900 will reboot and display the Welcome Screen with Regional settings.