Upgrading iphone 2G from 2.0 to 3.1 (redsn0w crashes etc)

Ok, so I just spend a good part of last night and this morning upgrading my first gen iphone from the OS 2 to OS 3 (3.0.1). It was a frustrating experience with use of multiple computers, countless reboots and now that I finally have my phone jailbroken and unlocked I can use it again (the upgrade bricked my phone, and I live in a country without any official Apple carrier so unlocking etc is a necessity). Because the information I used was often incorrect I'm publishing what I know did work.

The method I used was to:

1) Sync phone to backup on local computer
2) Use iTunes (latest version, 8.2.1.6) to upgrade to OS 3.0.1

This step locks the phone again, so now my phone displayed the unauthorized sim card message and does nothing. It's an iBrick till I can jailbreak and unlock it again.
3) Used redsn0w (win_0.8) to jailbreak and unlock.

Step 3 took me many hours and all the frustration. You need the 3.0.0 ispw as redsn0w doesn't support the latest 3.0.1 version yet (which is a small sms vulnerability bugfix from 3.0.0) but because the changes between versions are small it can be used on a phone that has been upgraded to 3.0.1.

The redsnow app was problematic, and would hang at the stage where the phone is to be rebooted. Searching for others with this problem revealed that disconnecting and reconnecting the phone from the computer would make it work and it did in my case.

But then after the reboot, redsn0w would crash. I searched high and low and found various recommendations to resolve this. I tried running it in compatibility mode with XP SP1 as well as in compatibility mode with Windows 95. I ran it as administrator, and various combinations of each. I made sure not to check "Icy" and only selected Cydia (even tried without it too). I read about using it in safemode, trying it on other computers and tried each. I read about making sure the ipsw is in the same folder as redsn0w and tried that. I read about rebooting the computer and tried that as well. I read about trying the earlier versions of redsn0w (0.71 and 0.72) and I hunted down each with no luck. I switched from a Vista desktop to a XP laptop, with the same results. Trying all of the above suggestions I found did not solve my problem.

Then I noticed that the ipsw file was the wrong one (and these are up to 300MB, so it's not trivial finding, downloading and trying new ones) for my hardware. I started hunting for others, and found a modified one (pre-jailbroken perhaps?) that was the right version but that redsn0w didn't recognize. The latest ispw for 3.0.1 isn't yet recognized either, and the others I had were for 3G and 3GS hardware, which redsn0w didn't throw an exception for, and just crashed with.

When I finally got a vanilla 2G 3.0.0 ipsw redsn0w worked differently, it asked for the 3.9 and 4.6 bootloaders which I found through a quick search. With this combination it worked, and I was able to jailbreak and unlock the phone and finally get use of it back.

For anyone else on the first gen iphone facing the same problem with redsn0w crashes make sure you are using the right ispw file. The file (for first gen iphones needing the 3.0.0 firmware) is named:

iPhone1,1_3.0_7A341_Restore.ipsw

Other files I tried that did not work were:

iPhone1,1_3.0.1_7A400_Restore.ipsw - This is the 3.0.1 upgrade with sms fix, and redsn0w currently doesn't recognize it.

iPhone1,1_3.0_7A341_Custom_Restore-A-U.ipsw - This was a modified ipsw that was described as already being jailbroken. It wasn't recognized by redsn0w.

iPhone2,1_3.0_7A341_Restore.ipsw - This is the one I spent so many times trying. It was recognized by redsn0w, but it's the wrong ipsw for my hardware (it is either for the 3G or the 3GS phones) but redsn0w didn't throw an error, it just crashed on me.

Hopefully by publishing my steps others in the same boat can avoid the same frustrations. All the pages I read (and I read several dozen) did not indicate that the incorrect ipsw would cause the redsn0w crashes and because redsn0w was not recognizing some ipsw files it gave the impression that it would reject incorrect ones.

So if you have redsn0w close on you repeatedly at the phone reboot stage, make sure you have the right ipsw version for your hardware as that might be causing it.