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So I'm trying to fix a friend's laptop. It boots up and shows the Acer logo then right after that, it proceeds to show a while unblinking underscore on the top left with a black background. What are the common causes of this? My original thought is it's just a loose hard drive. Unfortunately, I can't open up the laptop because there's a sticker for when it was last repaired. The place where it got repaired before is kinda far and we would like to try and fix it with external methods before having to go there.

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Usually that means:

  • System loaded sector 0 of the hard drive but it contains code that is causing the system to lockup. You might get this if the boot sector was overwritten.

  • Hard drive is having issues communicating with system due to bad connection or hard drive failure.

Create a Windows PE boot disk, and see if the drive comes up as C:. If it does, you could try the bootsect command to see if that will fix. If it does not, you are likely looking at something requiring disassembly of the laptop for further troubleshooting.

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I made one of those Hiren's Boot CD (is that what its called?) awhile back. I believe that's the same as a Windows PE boot disk right? t's supposed to help with recovering system and fixing possible errors. I tried it on another laptop and it works, on the Acer, it still proceeds to the non-blimking underscore. And yes I've set the boot priority. – Propeller Jul 7 '13 at 3:27
I think this can also happen with bad RAM. Try removing the DIMMs and replace with known good sticks. – Ben Plont Jul 8 '13 at 4:44
Thanks! RAM was the issue! – Propeller Jul 9 '13 at 4:07

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