(i have fixed this already on the spot by running quickpwn and restoring through itunes. but why did my iphone do this suddenly):

i just unlocked/jailbroke my phone last weekend. everything was fine. itunes came up with "update to 2.2.1?" i hit "cancel" (then went to preferences and disabled the auto-check)

so later that night, i drained my battery to 0 (it kept powering off around 4%, 3%, then finally at 0%) to re-calibrate my battery

i plugged it in to my computer to charge and about 20 minutes later noticed i was at the screen with the slider that says "slide for emergency" and i think a picture of a dock cable into a itunes logo.

at the top, my carrier still said t-mobile, and i think i heard a new mail notification as well

i tunes said "invalid sim detected!" and wouldnt let me do anything so, i fixed this by putting the phone in some sort of restore mode. then itunes recognized it as an apple boot something or other which let me restore it (shit-click on restore, browse to a 2.2 downloaded firmware version i originally used to jailbreak/unlock the phone). ran quickpwn.. everythings fine

but WHY ON EARTH would my phone do this? by draining my battery and plugging it into a pc with itunes, did apple detect it as a phone needing the stock firmware pushed to it?

i just want to make sure this doesnt happen again. i was able to restore a backup and re-sync everything. still need to put in the new mobileinstallation file, create the "documents" or whatever folders, etc but i think im running fine so far

since im new to all this, i wanted to make sure i didnt screw something up along the way to unlocking my phone to where this could randomly happen sometimes.

thanks

btw, yes this was a problem and was solved (back to back) but this post is more of a question to understand why this happened, what it means, and how to prevent it from happening again.

This has happened to me in the past. For some reason my officially activated on an official carrier iphone just went into emergency mode. I wasn't connected to a computer or did I kill my battery. I promptly connected it to my laptop and iTunes re-activated it. That was the only time it happened and that was several months ago. I hope it was just a fluke.

Same thing happened to my phone this morning - but itunes isn't recognising it..... HELP!! I've tried to do everything, but it's just not coming up as a device in Itunes......

I think I have the same problem, only I don't know how to fix it!

I got an unlocked 4gb 1st generation iPhone, so I can use my T-mobile sims card. I plugged it into my computer that has itunes, meaning to let it charge, but it has now gone into "emergency dial only" mode with the dock cable and iTunes logo also.
iTunes is also telling me that my sims card is invalid, and I have absolutely no idea how to fix this.

Please help! I'm desperate!

Originally Posted by superyoungwoon

I think I have the same problem, only I don't know how to fix it!

I got an unlocked 4gb 1st generation iPhone, so I can use my T-mobile sims card. I plugged it into my computer that has itunes, meaning to let it charge, but it has now gone into "emergency dial only" mode with the dock cable and iTunes logo also.
iTunes is also telling me that my sims card is invalid, and I have absolutely no idea how to fix this.

Sounds like you need to jailbreak and hacktivate again.

iClarified - iPhone - How to Unlock/Jailbreak Your iPhone 2G on OS 3.1.2 Using PwnageTool (Mac)
or on Windows iClarified - iPhone - How to Unlock/Jailbreak Your iPhone 2G on OS 3.0.x Using RedSn0w (Windows)