Right here's the crack:

I broke my old N900 after insurance etc. so I got a new one, it was all glitchy and slow so after a month or so I decided to flash it, I flashed my old one, l so I knew how to go about it, so using the same software as before I flashed it, but after it was complete it would take ages to load and not read my sim card.

So after reading on here I read that I actually done it wrong and was using old software, so I downloaded what I thought was new software (the third release(I didn't see the 'Latest' in bold on the newest version :| Lmao.)) So I flashed again with the 'new' software and it didn't work, so I read this post: http://talk.maemo.org/showthread.php?t=59007 and realised I was using the wrong software, so I followed the wiki exactly flashing the OS first (which I didn't do before I done the eMMC first..) with out the reboot command (-R). Then attempted to flash the eMMC but it won't work, this is exactly what happens:

- I get the phone into update mode,

- Open up command prompt, changing directory to C:\Program Files\maemo\flasher-3.5.exe,

- Run the command: flasher-3.5.exe -F RX-51_2009SE_10.2010.13-2.VANILLA_PR_EMMC_MR0_ARM.bin,

-Command prompt prints this:
Flasher v2.5.2 <Sep 24 2009>

Image 'mmc', size 255947 kB
Version RX-51_2009SE_10.2010.13-2.VANILLA
USE device found found at bus bus-0, device address \\.\libusb0-0001--0x0421-0x0105.
Found device RX-51 hardware revision 2101,
NOLO version 1.4.14,
Version of 'sw-release': RX-51_2009SE_10.2010.19-1.203.1_PR_203
Booting device into flash mode.
Suitable USB device not found, waiting.

-At this point my computer makes the USB disconnected then reconnected noise and my phone loses the USB icon for update mode, say nokia with no backlight on then the little loading dots come up, cycles about 10 times and then crashes and stays like that.

-The command prompt stays in the previous state and if I remove my phone and re-connect it in update mode, it won't find it.

I'm lost here. Any ideas? I am using Vista by the way.

Thanks in advance,
Ryan.

(I have read all the posts I can find on this and haven't seen this error yet)

(Took me about 10 mins to type this and my phone is still in the crashed state.)

Ok.. No need to panic at all... I assume you are not having Nokia PC Suite installed on your machine. May sound really crazy (You may call me crazy too, but doesn't matter as it worked for me. lol) but it seems that while flashing eMMC, the N900 goes from Update mode to PC-Suite Mode. In order to proceed, it requires the Nokia Cable Connectivity Drivers which is a part of Nokia PC Suite.

Heed my advice:
Format the device from scratch from the guide exactly as it says after installing the PC Suite. Trust me, I have gone through the same.

Now as you have stated that it is Vista, please do note that 64bit OS cannot flash the device. Therefore, if you are using Windows Vista x64 (Check by right clicking My Computer and clicking Properties) you'll need to either use a Windows XP machine or else you'll need to install a Virtual machine with XP on it.

(If you are using Windows XP Mode or something. If so, install the PC Suite on your XP Mode machine and make sure to click the USB menu on top and select the N900. May need you to do it around twice as it changes its modes from update mode for the first part and then to the PC Suite Mode in the eMMC flashing.)

Do notify me once you get through with these steps. If it still doesnt work out, I would try assisting furthur.