How can I remove the System partition

  RISC OS user 22:02 22 Jan 2016

I upgraded to Windows 10 on my Laptop but the boot was so slow, 1 minute 45 seconds and there is a legacy item which could be causing problems, "Unknown Device" appears after every re boot, I decided to use the DVD I burned to boot the PC and carry out a clean install. I removed all the partitions but was not able to remove the "System" partition but hoped that the clean install would deal with this, it did not. Whilst all my programs were wiped from the "C" partition by the "Clean" install I was still left with the old system partition which I assume holds various information such as Wallpaper, Account Name, Network setup etc., and I still have the "unknown Device" at boot up which still take the same time as before, about 105 seconds. I have looked at all the Microsoft Windows 10 help and FAQs and none cover "slow boot" only "no boot" which is not very helpful. The only actual problem thrown up by Windows 10 is that one of the drives is out of date and I have fixed that. The Laptop is an HP Pavilion dv6 6b08sa Entertainment Notebook which started life as Windows 7 Home which was updated to 8.0 and 8.1. The Unknown Device problem occurred at some unknown time with Windows 8 or 8.1, but the boot time as very fast. Does anyone out there have any ideas, please?

  lotvic 22:31 22 Jan 2016

Because it is not clear from the info you've provided, have a look at this page click here and in your disc management identify which 'system' partition (and it's size taking particular notice of the MB or GB) you are meaning. Be careful - if you delete the Active, Boot partition, your pc will not be able to boot.

  RISC OS user 10:30 23 Jan 2016

Thank you for your reply, please see click here which is a screen shot of the file which I believe is the problem. Am I not correct in thinking that with the Windows 10 DVD I can boot the machine from that regardless of the Hard disc info. I remember replacing a hard drive on my Desktop machine and I only had to format it and reinstall windows 7 from the back up discs. Would I not be able to do the same in this instance if I could only clear the Hard Drive?

  Fruit Bat /\0/\ 13:35 23 Jan 2016

You system reserve is too small for windows 10 (normally 350Mb) it will normally contain the windows boot files and bit locker encryption keys if you use an encrypted drive (so the PC can boot)

To start completely from fresh

  • Press Shift+F10 while installing Windows from the DVD, to open a Command Prompt window.
  • Type diskpart into the Command Prompt window and press Enter.
  • Create a new partition in the unallocated space using the diskpart tool. For example, if you have a single drive in the computer and it’s completely empty, you can just type select disk 0 and then create partition primary to select the first disk and create a new partition using the entire amount of unallocated space on the drive.
  • Continue the setup process. Select the partition you created earlier when you’re asked to select a partition to install to.
  RISC OS user 16:32 23 Jan 2016

Thank you FruitBat, not sure I really understand you suggestion, if the system partition is too small why can't I just enlarge it to the 350 MB and let the new Windows 10 installation use that, does it not over write the original as it does the C drive? I have tried to boot from the DVD and press shift f10 but do not get the required result. As an extreme work around I could install a 500GB hard drive into the PC after I have formatted it and made the necessary partitions, install Windows 10 and then clone the disc back onto my SSD and then re-install that into the PC which would be a reverse of what I did when the SSD was new but with Windows 8.1. One other thought would I need to partition the drive after formatting it I only formatted the new HDD when I installed it in my Desktop when the other one died?

  Fruit Bat /\0/\ 17:16 23 Jan 2016

Only files on system reserve are:


– System Volume Information

– bootmgr



These take up about 30Mb - Nothing to do with any network connection user or account files or devices, best just leave it as windows can't boot without it.

Look in device manager for the unknown device and select properties you should find an ID number from which we can find out what the device is and get the relevant driver.

CCleaner will show you what is trying to start with windows and possibly slowing you down.

  RISC OS user 21:41 23 Jan 2016

I have run cclean and Malwarebytes and still the boot time has not improved, there are no programs running at start up which would cause the delay, but I have stopped CCC which I do not understand how to set up anyway and I cannot see any difference with the PC without it. Re the unknown device I have tried to find a driver for it but there does not appear to be one, I have attached a screen shot of the information on it. click here That problem is always there even after what I believed to be a clean install of Windows 10 from the DVD which I burned from the ISO file I downloaded, it only seemed to remove all my programs but left my other detail such as account name, network setup, wallpaper etc. as I stated before.

  lotvic 22:47 23 Jan 2016

*unknown device on ACPI\HPQ0004* seems that is the HP 3D Drive Guard. Read click here

  robin_x 02:01 24 Jan 2016

I'm not sure whether System is being used or not, it is marked Active but it is too small.

Best to start again


Windows doesn't clear out the old MBR fully and other data is maybe coming from your Windows Account login to MS servers (Wallpaper etc)


Boot from W10 DVD and select Repair options (not Install) and navigate to Command prompt.

click here

Do a DISKPART etc CLEAN (see near bottom of above link)

It is not necessary to create any partitions.

Reboot from DVD and Install W10.

When you get to "Where do you want to install Windows?", click on Unallocated.

(if you see any other partitions there, delete them first (I am not sure if CLEAN has done that or just the MBR and Partition Tables))

Now Continue Install to Unallocated.

Windows will recreate and configure the partitions it needs, at the correct sizes.

  robin_x 02:04 24 Jan 2016

Don't have any other drives or peripherals connected except keyboard/mouse/touchpad

  RISC OS user 09:18 26 Jan 2016

Thank you Lotvic, I now do not have the unknown device after I down loaded the drive as per your post. Thanks also to all other posters, I have now given up on Windows 10 and reinstalled 8.1 which seems to behave correctly.

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