Unable to boot - Safe Mode stops after crcdisk.sys

yes I agree, all that and it does not relate to the problem,  the computer will not start so how is a person supposed to do half the stuff,  a useless fix by useless MS

It seems there are many different issues that can cause these symptoms, but as far as I can tell they are all hard-drive related. I had the same symptoms so I'll post my solution.

I have a Dell Inspiron 1545 Laptop

I was reinstalling Vista Home Basic on a new sata hard drive after the old one failed, and after encountering en error message while installing I tried using a the Vista Home Premium install disk I have for my other computer instead. I got no error message but the installation foze somewhere in the finishing steps, and after restarting I ended up with the neverendig startup bar, and - in safe mode - the crcdisk.sys freeze.

I suspected that the AHCI setting in the bios had something to to with it, but when I tried changing it to ATA i got an error message saying 'drive not found' or something of the like. I then tried changing the setting from AHCI to ATA and then reinstalling, and apparently this solved everything, because I reinstalled Vista Home Basic without any error messages and it seems to be working fine.

OK, finally I was able to boot in safe mode (msconfig / Diagnostic startup) - Someone mentioned it that "safe boot" does not work with F8 or F12 but with msconfig. Thank you!

So I saved all my data in safe mode ....

Did a clean installation and what surprise, no HDD troubles .... IT WAS A SOFTWARE problem and not a HARDWARE problem.

I'd like to know what Malkeleah (MS-MVP - Elephant Boy Computers - Don't Panic!) would say now ^^ ....

Conclusion: Save your time doing a clean installation even it hurts at the beginning since you need to backup/restore, installing/configuring all your apps .... But it's worth the effort. Otherwise you'll loose a lot of hours with trying to fix this.

Iam having the same problem, with two Windows 7 machines failing to start up at the same time.  I had a power failure, and found that the many "normal" troubleshooting cases I tried, including a fresh Windows 7 reinstall, all failed.  All of the machines uses SATA drives, one of the machines booted from an SSD drive.  I've experienced many many power failures and never had a problem the CHKDSK didn't fix, but in this case even a fresh install from the Windows 7 install disk would not fix the problem.  I reset the CMOS, removed the battery from my motherboard, tried every repair option I could find.  Eventually I disconnected all hard drives, bought a new drive and put that in, and installed Windows 7 on it.  But when trying to reconnect the old drives, one at a time, I could not even reformat the SSD drive, until I took it to my laptop  (a third machine, it's looking good at  96% complete).  The fact that the same hardware has two different results depending on which Win 7 machine I try to use it from tells me it's a problem with the original machine.  Yet I reset the BIOS settings, removed the battery, etc.  I don't get it.

The way this happened to two of my machines at home, and possibly a third at work (I'll investigate tomorrow) all at the same time, combined with the user above who reported it happening to 12 machines, tells me this is something other than a drive failure problem.  It's not hardware, unless a software update problem fried these drives. I believe all of the drives were SATA drives, so perhaps there is a bug in a Windows Update SATA driver or something, so that they were all put into some form of error state at the same time. 

At any rate, I found the message from Malkeleah to be thin on reading the problem and thick on abusing the poster who was trying to be helpful. I would report him for posting a message that offered no help but only insults, but it seems he is the moderator.  I agree that the long reply was not helpful because it was a shotgun reply trying to hit a target somewhere, but at least he was trying to help, and none of the insults help resolve the issue, which seems to me to be two-fold:

1. some update, perhaps SATA driver, results in an unbootable hard drive.
2. crcdisk.sys cannot deal with this situation and hangs.

If the second problem was at least detected and resolved, perhaps it could report whatever the condition was that would have otherwise put crcdisk.sys in that state, and that would provide a clue here.

Paul

I beg to differ.  This problem is not hardware it is software. I am trying to repair 12 laptops that all went down with this problem at the same time. System hangs on startup, forever and SafeMode shows the hang after crcdisk.sys loads. The crcdisk.sys is the cause of hard drive corruption (mbr and others), however, the driver that has been corrupted and is the initial sickness I have not yet identified.  Apparently caused by a Microsoft update installed on a system infected by some trojan, judging from most of the info I have gathered over the past few days.