Posts Tagged registry

Recover from an corrupted XP registry

Posted on Monday, February 9th, 2009 at 2:42 pm

Hello again, its been a while since my last update. I was repairing a laptop this weekend, one that had a corrupt registry. It was displaying the following error message when booting: “Windows XP could not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SYSTEM”.

I brought up Google and found a number of sites that describe the error, some from MS itself, but most of them are overly complex and offer little in the way of help. I was just about to resign myself to reinstalling when I ran across a link from this site: Recover from an XP Corrupt Registry.

It covered everything that I needed and worked like a charm. I did make one change from the posted instructions; instead of booting into recovery mode each time (which takes forever via the CD) to copy files, I just plugged the laptop’s hdd into an external enclosure and did it that way.

Easy peasy.

Enabling AHCI on Vista

Posted on Wednesday, December 10th, 2008 at 1:45 am

Greeting.   I ran across this the other day and immediately thought of this website.  Its one of those things that I will use now, then forget about and in six months to a years time when I need it again, it’ll be gone.

I hadn’t bothered to use the AHCI drivers when I installed Vista a while ago, but I’ve been hearing more and more how its a good thing (as long as your hardware supports it), or more to the point, the NCQ is a good thing.

Some time in the past, I tried to get XP to switch to AHCI after install but never had any luck; there are instructions out there and I don’t doubt they work for most people, but I either had some sort of incompatible hardware or pebkac (problem exists between keyboard and chair) going on because it just wasn’t meant to be.  After that incident I’ve been a bit leery of AHCI.

Anyway, I decided to try it all again and this time it was remarkably easy to do.  Just a simple registry tweak, reboot and change your SATA controller to AHCI in the BIOS and that’s it.  I was reasonably impressed that it went so smoothly.  I”m still waiting for some catastrophic data corruption; I’ll let you know if that ever happens.

I’d rate this a 3 on the difficulty scale, and a 6 on the potential bad idea meter.

Instructions:

  1. Go to: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci
  2. Modify Start
  3. Change the value to 0
  4. Reboot
  5. Go into bios and change sata controller to AHCI (its probably on IDE right now)

That’s it.

Reference (from Microsoft):

http://support.microsoft.com/kb/922976