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My friend has a problem with her laptop. I offered her my help, but unfortunately I can't fix it.

The thing that happened is that once she started her Toshiba, it show a blue screen with some hardware error(never shown again). So I get that laptop and try to fix it.

I tried to start it. It gets stuck while booting system. Just a Win logo visible with a "System is booting" or something like that. And, you can see that endlessly. Just nothing happens.

So I tried to start it in safe mode. It was showing a list of files which have been booted. It gets stuck on ...\classpnp.sys. I tried repair using CD, bootable USB, etc. Then I tried to boot portable Ubuntu from USB. Here, everything runs fine. Everything was OK! It was really strange for me because I thought some hardware is off (I thought it might be the motherboard). But when Ubuntu runs fine?

Next day I tried to reinstall Win. I found out that it's not possible. So I get the disk from her laptop and put it in mine. I successfully installed Windows 7 32bit on it. On my laptop it runs fine. I tested also HDD and has no issues.

Next I put HDD back to her laptop, tried to start but it gets stuck on ...\disk.sys. I don't have any idea what the problem would be (Ubuntu from USB runs fine!). What can be wrong? Can it be a SATA cable to HDD or what? How can I find out or test it?

Please help guys.

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"I tried to reinstall Win. I found out that it´s not possible" - could you describe why you were unable to do it? – gronostaj May 30 '14 at 13:07
@ gronostaj It wasn´t possible to reinstall it on the "wrong" laptop(on that toshiba). But when I take away that disk and put it in my laptop I reinstalled that Windows. When I tried it on that toshiba, windows installation files has been copied and than it just tried to boot old win and stucked. – Gondil May 30 '14 at 13:17
I got it, but it may be important what prevented you from installing on the original machine? – gronostaj May 30 '14 at 13:20
@gronostaj Yes I also think that is really important that it wasn´t possible to reinstall it on the original. But can´t figure out what can cause it. So I though that it can be SATA cable. I also forget to mention that I also tried to boot Win 8.1 from my SSD connected to that wrong Toshiba and same result-stucked. – Gondil May 30 '14 at 13:22
Foreign instances of Windows just won't boot, it's not related to this problem. I'm trying to guess what caused this issue, but I need some more details. Did you see any error message, or was some button greyed out, or you couldn't boot from external media, or what exactly was wrong that made reinstalling impossible? "Wasn't possible" is not good enough :) – gronostaj May 30 '14 at 13:29

What was wrong:

I guess the filesystem had been damaged. Live Ubuntu ran fine, because it didn't use HDD at all.

First of all, you should check HDD's SMART status. If any parameters are out of the safe range (especially if there are any bad sectors) then the drive is dying and should not be used, because the damage will increase quickly. In this case you should replace the HDD.

Why you couldn't reinstall Windows:

Windows is bound to the hardware it was installed on. Unlike most Linux distros, it won't work when moved to another PC. You can strip it from any hardware-specific parts with sysprep and related tools, but it's quite complicated and probably is an overkill in this case.

You weren't able to successfully install Windows from a disk dedicated for different laptop for the same reason; it was preloaded with hardware-specific drivers etc.

How to fix it:

If you have a regular Windows license key, then download a generic ISO and burn it or use the Download tool to install from a flash disk.

OEM license key that can be found on the sticker on the bottom of a laptop may not be accepted by generic installer. The laptop should be equipped with a recovery partition that allows automated OS reinstallation. Exact methods of booting into the recovery mode differ between laptop manufacturers and models. The routine should be described in the manual.

If you can't access the recovery partition for some reason, laptop's manufacturer should be able to provide Windows disk, but you'll probably have to pay for it.

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I checked the HDD using HDTune and all sectors are OK. SMART status is also alright. So in my opinion it´s not a HDD issue. I have also original Win7 generic, and that was installed on the disk. OK it can be problem that it was installed through my laptop, maybe I can try to make bootable USB and try to install it on that "damaged" laptop but I don´t believe that it will run correctly. But question is: "Why it suddenly stucked on classpnp.sys?" (I mean That laptop was used for maybe 3 years well and then stuck.. I mean before reinstall)-it ONCE shows this screen – Gondil May 30 '14 at 14:46
Once every time you reinstall Windows? That's strange. If it had appeared just once I'd be 95% sure it's a filesystem/HDD issue. I'd try installing from the generic ISO now. – gronostaj May 30 '14 at 16:59
She told me that it has been shown just once. And during my "work" on it, that screen hasn´t been shown. Yes I'll try to install Win with ISO but now I don't have that laptop so I surely post a comment what happend. Thank you very much for your interest in my problem. – Gondil May 30 '14 at 18:31
Hello my friend. I´m here again. I got that laptop home and now I can work on it. Yesterday I made 5 videos to describe what happens. (1)Win7 standard boot stuck on booting screen. (2) Win7 stuck after disk.sys in safe mode. (3) That same Win7 booted well on my ThinkPad(I just moved HDD from Toshiba to my laptop). (4) As you advised me, I tried to install Win7 in that "broken" toshiba using original Win iso on USB but stucked. (5) I booted Ubuntu from USB on broken Toshiba and works fine. Please can you look on it? Vids: – Gondil Jun 7 '14 at 6:51
How long have you been waiting for the installer to start from USB? – gronostaj Jun 7 '14 at 9:03
up vote 0 down vote accepted

So finally I made it. For me, problem was in touchpad(so as I though in some HardWare).

What have I done:

(1) I format disk partition with System(using other laptop)
(2) Insert a disk back to "broken" laptop and start it.
(3) Boot in the BIOS.
(4) Turn off all hardware you can(LAN, WiFi, pointing devices,...) except USB ports(used for
        Win install from bootable USB)
(5) Insert bootable USB with Win .iso. Restart laptop and choose device to boot from (USB)
(6) Install Win
(7) When everything goes fine, restart laptop and in BIOS repeatedly turn some hardware on 
        and boot to Windows. When Win works fine hardware should be OK. When not. There is
        some issue with specific hardware(hardware is off, there is wrong driver installed, cable connecting device to motherboard is damaged, etc.)

Hope this help somebody.

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