Originally Posted by Nik_Ind

Honestly, I am fed up! Tried everything, but nothing works. My N900 just won't go into flashing mode. IT JUST WON'T!!! I've never had any problems with my other Nokia cellphones, and this experience has left a bad taste. I've given the device at Nokia Care Centre. Once it is in it's original state, i'll probably just sell it off. I am using a 32- bit windows. The binary and flasher work fine, but the device won't go into usb mode due to which the flasher does not detect it. Just some bloody looping keeps happening. Fully charged battery too did not help. Super frustrated!

Originally Posted by TA-t3

I have finally managed to recover my N900. Story follows:

1: Charged the device fully.
2: Started the 1.1 over-the-air upgrade
3: Looked fine. Until I noticed that wi-fi didn't work.
4: apt-get upgrade -s indicated that it had only upgraded half-through.
5: application manager still showed Maemo5 as upgrade. Selected it again.
6: After 5: application manager still showed Maemo5, and 21KB left to install.
7: N900 started showing UIBFS errors in 'dmesg' in terminal.
8: It suddenly died and would not power on.
9: Attempted reflash. No go.

At this point, and after hints from posters above, it turned out that the N900 battery was actually discharged (even though it had been fully charged before attempting the initial upgrade). I verified this by measuring the battery with a multimeter.

10: Bought stand-alone charger, recharged battery, checked with multimeter.

I still could not reflash, even with fresh battery:

* Pressing 'u' then connecting N900 to Linux computer did not result in anything (it did not go into reflash mode)
* Connecting, then re-inserting battery in N900 did not work either
* Checking DMESG output on Linux computer while connecting N900 showed no awareness on the USB bus at all
* Removing and re-inserting battery on N900 resulted in a 0.2 second cycle of USB connect, 'Nokia USB ROM' message (or some such), USB disconnect cycle. There was an USB event on the PC _only_ if re-inserting the battery, never if just connecting USB cable (with or without 'u' key).

I finally managed to fix everything by 'cold-flashing' the N900. This is what worked:

1: Make sure that 'usbfs' is mounted on /proc/bus/usb on Linux laptop
2: N900 battery fully charged, as indicated above
3: Remove battery from N900
4: Connect USB cable to Linux computer and N900
5: Execute the following on Linux computer (as root, or with sudo)

Code:

./flasher-3.5 -c -h RX-51:2201 -S usb -F RX-51_2009SE_2.2009.51-1_PR_COMBINED_MR0_ARM.bin -f -R

6: Re-insert battery in N900
7: Voila! N900 reflashes, then reboots.

Note that I did attempt step 5 on a desktop Linux computer with USB 2.0, but could not get it to work. Presumably the flasher didn't manage to detect the exceedingly short USB connect event when the battery was inserted. I finally got it working with an (old) laptop with USB 1.1.

This was hairy stuff. Apparently boot loader was destroyed on the N900, or something else that made the normal (warm) reflashing fail. NB: Note that "-S usb" is needed with -c, and -h needs "RX-51:2201". The wiki doesn't mention "-S usb" IIRC, and without it it'll try to cold-flash over the serial device instead. The wiki also says the device id (2201) should be visible under the battery, that is not the case.

Things would have been easier if the N900 could run on AC alone, like the Pandora.

Originally Posted by shani

good to know this but can i do cold flasher on window xp or window 7 or mac
i dont have linux pc
so kindly please tell me as soon as possible
that how to cold flash on window xp or 7 or mac
waiting for reply