Two possibilities fit that particular description:
1: Your OS install is completely toast and you need to reinstall
2: Your HDD has gone titsup and needs to be replaced
Since the second option necessitates an OS reinstall anyway, you may as well try that option first. Might get lucky, who knows. Otherwise, time to find out if there's any time left on the warranty to make a claim on the HDD. If not, well, it probably couldn't have happened at a worse time because retailers everywhere are gouging people on HDD prices thanks to the flooding in Thailand where most HDD's are made. So be sure to buy sooner rather than later if the OS restore doesn't do the trick, because it could be months before those factories are back up and going, and prices are likely going to only go up in the mean time.
Well i have Windows 7 in my HP laptop. when i turn my laptop on it shows the HP logo and says "ESC to boot menu". If I let it run to windows, a white underscore keeps flashing for hours and hours in black screen and it wont start windows. If I go to the boot menu by pressing ESC the same underscore thing happens. please help me i just want to install linux and get rid of this.
help me ASAP

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