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w520 keeps looping back to startup

W500/W510/W520 and W700/W701 series specific matters only
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w520 keeps looping back to startup

#1 Post by elizalew » Mon Oct 26, 2020 4:06 pm

I have an old W520 laptop originally installed with Windows 7. I decided to upgrade / install Windows 10 on it. After pressing ON button, it keeps looping back to the start up stage (To interrupt normal startup, press the blue ThinkVantage button). I tried this blue button as well as F1 or Del with F12. Nothing seems to interrupt and goes to the Boot Menu.. that I need to use the USB drive to start install Windows 10 from scratch.

Please help..

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Re: w520 keeps looping back to startup

#2 Post by atagunov » Mon Oct 26, 2020 4:33 pm

Hi, sorry to hear about this. How did the looping behaviour start? What prompted it?
Have you tried removing your HDD/SSD? Does it still loop?
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Re: w520 keeps looping back to startup

#3 Post by Vopu » Mon Oct 26, 2020 5:03 pm

Hi , Somehow it seems unclear to me what you are trying to achieve, Did i get this right? , :eek:
You ARE trying to to install Win10 , NOT have installed but now it is a continious loop ?
OR Are are you simply trying to go into your bios to change the boot priority in order to install the Win10?
-What is the source of your Win10? Is it a download / what is the source media?
-What SW have you used to make your bootable USB Win10 media?
-You mention Del with F12 combo ? F12 is temporary boot priority. not Del+F12
-Is/was your Win7 working before you attempted to install Win10?
- What key are you pressing exactly to get into bios ?

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Re: w520 keeps looping back to startup

#4 Post by jursky » Wed Oct 28, 2020 11:52 pm

Make a bootable USB with Windows 10 installation or use DVD - if you have one, then boot it during laptop start (F12 key, I believe). Once you'll be at fresh Windows installation screen press together Shift + F10, it should bring on Command Line, then type following:
> C:
> dir
It should print out something like this:
Volume in drive C is Reserved
Volume Serial Number is 2C0B-A82C
Note: that is, if you have created a Reserved 100-500MB partition during Windows installation.

If you land on another drive, then try other possibilities like D:, or E:, of F:, one of them should be right. If you don't want to guess name of Reserved partition, you can use DISKPART utility for that:
> list vol
It should print out something like this:

Code: Select all

DISKPART> list vol

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 0         res          NTFS   Partition    100 MB  Healthy    System
  Volume 1     C   win10evo1TB  NTFS   Partition    122 GB  Healthy    Boot
  Volume 2     D   evo1TB       NTFS   Partition    757 GB  Healthy

Note: in my case I am running that on correctly running Windows so I have "res" partition hidden (without any letter assigned - when you run that in Windows installation command line (SHIFT+F10), every partition has some letter assigned).
Note 2: it is also possible that you might have no "reserved" partition at all, in that case all booting files might reside on main drive where Windows is installed - in that case, navigate yourself out of diskpart (exit exit) and try to jump accross drives, looking for \Windows folder).

Then type:
> cd boot (Note: do not mind if dir listing did not print any record of boot folder in that location, that folder is hidden by default but you can still navigate to it if you specifically mention that you'd like to go there)
Then type:
> attrib -h -r -s BCD
It should remove read-only hidden system file flags from hidden file called BCD; now you should be able to delete the file:
> del BCD
Then type following commands to create new repaired BCD file:

Code: Select all

bootrec /fixmbr
bootrec /fixboot
bootrec /rebuildbcd
When you're asked if you'd like to add your Windows installation to the boot list (something like E:\Windows or whatever), answer either (Y)es or (A)ll (add all found to the boot list).
That's it, your BCD should be restored and Windows should start booting with next restart (remove USB/DVD from laptop, you can close Windows installation by just clicking on X on its main window).

Of course you may have completely another problem, so this is just a blind shot, but maybe it will help you. It helped me a lot of times to correct non booting Windows.
X230 i7-3520M (Nitrocaster Rev.6 + 13.3" FHD 99% sRGB IPS panel SHARP LQ133M1JW02).

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Re: w520 keeps looping back to startup

#5 Post by elizalew » Thu Oct 29, 2020 3:03 pm

Thanks to all who responded my request. It turned out that it's the mother board has a problem and need to be fixed.


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