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I can't run my Windows 7 64bit.

I tried:

  • System repair – hangs at the repair screen
  • Start normally – hangs at the Starting Windows screen
  • Start in safe mode – hangs at the classpnp.sys file
  • Start in safe mode with command prompt – hangs at the classpnp.sys file
  • start in safe mode with networking – hangs at the classpnp.sys file
  • Start in "don't force restart": Error like unmountable_boot_volume

I even tried to put in the Windows 7 disc to do a re-installation and it hangs at the Starting Windows screen.

I can access to my hard disk and my files with Ubuntu Live.

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Yes, I know what's it. I have a good answer for it here:… – Jet Jun 10 '13 at 13:22
If all else fails you can try booting from a Linux LiveCD/USB, backing up your files and completely deleting all Win7 partitions (or all partitions) using GParted or similar. Then try reinstalling. If Setup fails with an empty drive too then you have a hardware problem. Test your HDD (use HDD manufacturer's testing utility), RAM (use memtest/memtest86+) and so on. – Karan Jun 10 '13 at 18:25

Most likely your hard drive is failing in the sectors your windows partition is located. This explains being able to boot your linux OS. Copy files ASAP through linux and replace hard drive.

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you should do the following to repair the corrupted files:

Insert the Windows 7 DVD in the computer's DVD drive

Run like you are going to install windows again

Boot from CD/DVD drive Click Install now.

When we are prompted to input the product key, please click Next without inputting any key. The setup wizard will prompt and ask if you agree to install Windows 7 without the key. Please choose to confirm.

When you reach the "Which type of installation do you want" screen, click Upgrade to upgrade the system files of Windows 7.

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"I even tried to put in the Windows 7 disc to do a re-installation and it hangs at the Starting Windows screen." – Karan Jun 10 '13 at 18:19

First, before you do anything else , check your backups. If you have important files of which you have no backup then boot Ubuntu again copy them.

Next there are a few thing you can do. Start with these:

  1. The problem unmountable_boot_volume is often causes by disk corruption: So run checkdisk from the windows DVD (or windows pen drive). Boot, drop to a console with Shift-F10 and run checkdisk.
  2. Or remove the harddisk, plug it into another windows computer and run checkdisk.(Hopefully needless to say: Booting the windows installation from the other computer.)

If that does not solve the problem you can always restore a backup, or reformat and reinstall, but that is a lot more work.

Also try looking at the log files (e.g. the event viewer logs, or /windows/nbtlog.txt). On my windows 7 PC that last log looks like this:

Loaded driver \SystemRoot\System32\Drivers\mup.sys
Loaded driver \SystemRoot\System32\drivers\hwpolicy.sys
Loaded driver \SystemRoot\System32\DRIVERS\fvevol.sys
Loaded driver \SystemRoot\system32\DRIVERS\disk.sys
Loaded driver \SystemRoot\system32\DRIVERS\CLASSPNP.SYS   <-----
Loaded driver \SystemRoot\system32\DRIVERS\avgrkx64.sys
Loaded driver \SystemRoot\system32\DRIVERS\avgloga.sys
Loaded driver \SystemRoot\system32\DRIVERS\avgmfx64.sys
Loaded driver \SystemRoot\system32\DRIVERS\avgidsha.sys
Loaded driver \SystemRoot\system32\drivers\cdrom.sys
Loaded driver \SystemRoot\System32\Drivers\Nul

It is quite possible that ClassPNP is not the problem, but the files after it is the one locking up your system. (In the example shows that is avgrkx64.sys, part of AVG antivirus. In your case that might be a different file).

Also, did you change anything before your windows stopped booting?
If not, can you add that to the OP?
If you did, please add what was changed.

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thanks for your helpful post ;) i didnt change any option . what is your mean about OP? – user230267 Jun 10 '13 at 12:43
OP is short for Original Post. – Hennes Jun 10 '13 at 12:50

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