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Whenever I start my laptop it just displays an underscore in the top left corner. It makes no POST beeps or anything.

What can I do to fix this?

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this doesn't look good ... – user8228 Sep 4 '09 at 20:52
what operating system do u have ? can you see the manufacture logo on the screen when u boot up ? – user8228 Sep 4 '09 at 21:00
question starter has already stated he heard no post beeps. It's not an external boot issue. BIOS cannot even POST. – caliban Sep 4 '09 at 21:01
At lack of POST beeps does not indicate it didn't get past POST. I think Revolter has the right idea - more information is needed for more specific help. – Insomnic Sep 4 '09 at 21:06
"no post beeps" doesn't preclude that the BIOS didn't get past POST. Is anything displayed on the display before the system stops at the cursor? – hanleyp Sep 4 '09 at 21:06

This situation is commonly seen when a drive that is unformatted or boot sector that's corrupted tries to be accessed. The computer is getting past POST and tries to run what it finds on the hard drive and can't so just sits waiting for the next command. This is often seen when an image is being pushed to a hard drive and is interrupted. Another common situation is the computer is trying to boot a USB key or other external storage device that doesn't have boot information.

You can also try using the FIXMBR and FIXBOOT commands accessible in the Windows recovery console found on your Windows installation CD (if this is a Windows box). You can also try a basic "Windows Automatic Repair" option from the same disc. Connecting the drive to another computer via external device or as a slave drive often allows you to at least collect the data if the above commands don't work.

Simply unplugging the external storage device will solve the problem if it is an external device that's causing the issue. Also changing the boot order in the BIOS should allow you to keep the external device plugged in on subsequent boots.

Beyond these options I think more information will be required but hopefully this will be a good starting point.

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Comments are helpful when downvoting. – EBGreen Sep 4 '09 at 21:13
I've tried putting in the windows installation cd but it still hasn't done anything, and I wasn't able to access the bios part to change the boot order because I didn't have the bios password. – Samurai Waffle Sep 19 '09 at 22:50
Getting into the BIOS will be an important step - try to find out who your motherboard manufacturer is and whether there is a default password / how to reset the password. – Ciaran Aug 19 '11 at 15:14

Do you have an SD card plugged in anywhere? I have seen that hang a boot in this fashion before.

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Typically, it will ask you for a boot device when that happens... – JFV Sep 4 '09 at 20:58
Doesn't on my machine at home. :) – EBGreen Sep 4 '09 at 21:12
JFV: No, I have 1 non-bootable USB stick that, when I forget to remove it, halts my PC the same way. – Henk Sep 13 '09 at 20:46

Try these :

  1. Change your RAM, or if you have 2 sticks of RAM, alternate plugging them out.
  2. Plug out hard disk, all unnecessary peripherals. See if PC boots and POST.
  3. Plug out battery too.
  4. Put your ear to the notebook, any high-pitch or weird sounds?

Let us know.

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I've had this myself, and it indicated problems with my motherboard, I could solve it by disconnecting my battery and using the power adapter only.

This ofcourse defeated the mobility of the laptop...

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Sounds like the motherboard/processor went out on you. I've had a lot of clients come to me with the same issue. Lately, it's been HP laptops. If you have an HP, look up for a 'Limited Warranty Service Enhancement'

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This would cause nothing on the screen. A flashing _ requires the processor and most of the hard ware to work. – Mike Cooper Sep 4 '09 at 21:23

Are you able to see the BIOS load? (Black screen usually with the brand of laptop logo) If yes you might be able to boot from disc and reinstall windows. Your going to lose everything if you don't have anything backup on a disc or drive. Ofcourse this would be one of your last options.

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I had this happen when the computer is set to boot to USB before the internal hard drive, and you have an external usb drive (hard drive or flash drive). It tries to boot to that drive, and nothing happens. Either unplug any usb drives, or change your boot order in your BIOS.

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I had this exact problem on my computer a few days ago, it was bad RAM.

Same symptoms, no POST beep, just the flashing underscore.

Try taking out a stick at a time and see if you can get it to boot.

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I will say : turn off your laptop, unplug the battery and the charger, and hold the power button for at least 20 seconds. then, plug the battery and try again.

this problems may be temporary, turn it off and try again in 2 hours...

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+1 - Had a friend of my spend hours with Tech Support and to finally try this and his machine booted no problem after doing what you mentioned. – Hondalex Sep 4 '09 at 21:51
it sounds so silly and yet it often works miracles :) +1 – Molly7244 Sep 4 '09 at 21:54
What does pressing the power button for 20 seconds do when there's no battery present? – Ciaran Aug 19 '11 at 15:13
This will discharge the motherboard of static – user8228 Aug 19 '11 at 20:19
Got anything to back that up? – Ciaran Aug 19 '11 at 21:12

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