Boot/login problem ... getting nowhere!

Hi to all forum members, I hope someone can help me please.

My Intel iMac crashed yesterday for no particular reason, ending with a blue screen and endlessly turning cog. When I immediately shut down and restarted, OS X got to the login screen and then cut straight to another blue screen followed by exiting to terminal ("Darwin/BSD", text login etc). When I entered my login, it went back to the blue screen and no progress.

Tried this a couple of times with no joy; a few times there was blue screen only, no terminal.

Tried Safe Boot but same thing happens. Ran Apple Hardware Test, everything checks out OK. I can boot with Install CD, and I have run both Repair Disk and Repair Disk Permissions. Still no luck. Ran crons from Terminal window. No joy. Finally tried resetting PROM, but still no change.

I am at a loss as to what to try next. I have my documents backed up but haven't backed up my Entourage email for a couple of weeks, and I am concerned I will lose these messages if I reinstall OS X.

Does anyone have any advice or suggestions? Any help greatly appreciated.

Do an "Archive and Install" from the DVD that came with your mac. It will reinstall the OS but preserve user accounts and data. You may also need to reinstall some apps if they don't work correctly.

Yeah, I thought that might be my only option; haven't done it before (new to Mac) and wasn't sure how much it would keep. Thanks for the advice.

Anyone have any ideas what the cause might be? I suspect it all happened after I installed some Canon image software that came with a new digital camera ... won't be trying that again.

It's possible that the Canon software was not a universal binary. (Intel Mac friendly)

I've seen HP software that installed a startup item that caused the Mac to hang at boot.

MacsWork -- I suspect you're right, as I stupidly didn't check that the Canon software was Universal before installing it. Won't try that again.

Just talked to Apple support, who agreed an Archive & Install may be necessary, but suggested resetting the System Management Controller first, just in case that fixes it.

Don't trust that all my settings will be preserved (too long with Windows!!) so used Ubuntu Linux live DVD to copy all my user dirs to external HDD last night.

Hopefully my (up until now) shiny & reliable iMac will get working again soon.

Until next time ...

mokjok said:

Yeah, I thought that might be my only option

Click to expand...

It isn't your only option, it should be your last option.

http://docs.info.apple.com/article.html?artnum=106464#symp1

D3v1L80Y said:

It isn't your only option, it should be your last option.

http://docs.info.apple.com/article.html?artnum=106464#symp1

Click to expand...

Point taken ...

Thanks for the reference ... I actually saw that article while hunting through Apple support but was turned away by the fact that it seemed to specifically refer to pre-Tiger OS X; wasn't sure if all the tips would work or if I would make more trouble for myself.

I can't use tips 1-3 anyway because I can't boot into Safe Mode. I'm tempted to try the others, though, before I commit to Archive & Install.

Of course, all of this needs to wait until I get home from work this evening, so I'll let you know if anything works. Thanks again.

Problem solved (kinda) .

In case anyone else has the same problem, thought I post the outcome.

After much hunting, it seems the problem was that the loginwindow.app was missing or deleted from the Coreservices directory. As a result, OS X couldn't log in and defaulted to the Darwin/BSD console, similar to a server mode.

Being a Mac newbie, I had no idea how to obtain or restore loginwindow.app by itself, and so I have ended up doing an Archive & Install, which seems to have worked OK, although I haven't confirmed that all my apps work.

Unfortunately, I had followed Apple Support's advice to reset the SMC by holding down the power button while plugging in the power cord, which has resulted in my iMac sounding like a jet engine! But there seems to be an easy reset for this which I'm just about to try, courtesy of the Apple website.

Thanks for the advice offered, here's hoping no one else has the same trouble.