Strange new Drive created by Windows 8.1 update


  • After updating my Asus laptop to Windows 8.1 I noticed a new drive has appeared in the Tools/Optimization screen, and also in the Disk Management screen.  I have tried to attach screenshots but the stupid site won't allow me to because it says I can't attach images until my account is verified, even though I answered the email to verify the account.  Before I had the OS, Recovery, and Restore drives showing up, but now there is an additional drive titled ....\\?\Volume that wasn't there before.  Also, in Disk Management, somehow I now have 5 partitions when there were only 3 before.  I have never created a partition on this machine, so I don't know why 8.1 would add all this in addition to the Recovery and Restore partition that was already there.  I updated my wife's Surface to 8.1 RT and she also now has these mysterious new drives with all the \\ and question marks.  How can I get rid of this junk?  I have always been a supporter of MS, but I don't like it when they take over your machine and do this kind of stuff without permission.

    Tuesday, October 22, 2013 2:23 AM

All replies

  • I'm still trying to post a screenshot of this issue and the system is still saying my account has to be verified.  Will post screenshots as soon as I can.
    Tuesday, October 22, 2013 2:15 PM
  • You can host your screenshot to another website such as Flickr or Photobucket and then post the link here.

    I did a test update yesterday because I saw other users report new partitions had appeared but I could not replicate. Do you have a memory card reader in your notebook?

    Tuesday, October 22, 2013 3:52 PM
  • Yes, I do have a memory card reader in the Asus UX51VZA notebook.  It didn't have anything in it while I was updating it, but I do have the reader.  I'll work on providing the screenshot when I get home to have access.

    As mentioned, I upgraded my wife's Surfact to RT 8.1 and it created the same new partition on hers also....with the same format of ....\\?\Volume followed by random numbers and letters. 

    Tuesday, October 22, 2013 6:35 PM
  • Hello Davidoo1, First and foremost I would like to confirm I have had the same problem as well on my acer and I only bought it a week ago also it happened after win 8.1 update. Apart from this i have had no other problems with the update and my pc is running fast an fine but just like you I would like to know what this is as I had the 3 partitions before the update the: c drive the push button reset and recovery but after win 8.1 update I have a unidentified partition beginning with \\?\ volume also to add like you in the partition management I have 5 just like you.

    Secondly this forum was hard to find I and i will also try upload screen shots and i suggest we get this forum out there some how so we can get to a speedy solution with out having to revert back to win 8. 

    Thanks if you have questions don't hesitate to contact me.

    By "NeedsHelpPlease"

    Tuesday, October 22, 2013 7:40 PM
  • I got the same mysterious new volume in my C:

    It starts with \\?\Volume{ ....

    On top of that it shows its heavily fragmented but Disk Optimization cannot fix it.

    Wednesday, October 23, 2013 12:39 PM
  • Hello eSetter.  I still don't know why I got the same mysterious drive, but I was able to resolve the issue of it being fragmented and defragment or "optimize" it.  The other problem I noticed was that in the Media Type for the Disk Optimization screen it showed my Solid State Drives as regular Hard Drives.  It took me hours and many internet searches to figure it out, but I solved that issue with the procedure outlined below.  Still, I don't know what this new drive is for, but it is at least optimized.  Once you get the drives correctly tagged as SSDs (if you have SSDs) then they will run the "Trim" command and be optimized correctly.  Here is the procedure below......

    This has to do with the Microsoft Windows Experience Index not being run yet on
    the updated OS. Problem is MS removed the GUI for this in 8.1. Here is the text
    of what I found and how I fixed it to now show SSD for Media Type. One
    additional thing is that I had to go to the system folder
    Windows/Performance/WinSAT/datastore and delete the Disk_Assessment XML file so
    running winsat prepop would re-label the SSDs correctly. What a nightmare just
    to get this to show correctly.

    Now I still don't know how I got the new
    partition with all the \\?\ in the volume label.

    Here's the text from
    the solution I found....................

    The problem is caused by
    Microsoft WEI (Windows Experience Index) not being run (its even removed from
    the GUI in Windows 8.1).

    To help Windows 8 and Windows 8.1 users, the
    core code that does this is still in Windows, but only accessible from the
    command line in 8.1.

    To get the SSDs to be correctly listed:

    Install the latest RST from Intel (currently 12.8 from Aug'13). 2) Go to an
    admin cmd prompt 3) Type: winsat prepop

    This will run all the tests on
    the computer and reprofile it. This includes correctly tagging RAID0 SSDs.

    Wednesday, October 23, 2013 1:31 PM
  • I would like to ask if all these problems will go away if I reset back to win 8 using the recovery partition and will it delete the mysterious partition?

    I no longer care for 8.1 I prefer to go back to 8.

    Thanks I hope for a reply soon.

    Wednesday, October 23, 2013 3:01 PM
  • I Reset my pc back to win 8 and the unknown drive was still there I tried your solution and its still there labelled with that question mark and back slash etc also I still have a total of 5 and in the disk management it still has them with out names. 

    What should I do now ?

    Wednesday, October 23, 2013 8:42 PM
  • NeedsHelpPlease, I'm not sure if your request for help is directed towards me or not.  My "solution" was only regarding being able to get the Solid State Drives to correctly show in the Optimization tool as SSDs and not Hard Drives.  I still have the same issue as others where I now have 5 partitions with the ...\\?\... drive that I don't know what is for.  Unfortunately, my guess is this is permanent and probably the only way would be to format the drives and do a "clean" windows 8.1 install.  I'm going to hold off on doing anything at the moment as my computer is working fine and maybe MS will come up with something in an update to properly label the drive or get rid of it if it is not needed.  I'm just one of those that is annoyed when drives show up on my computer unannounced and I don't know what is in it. 


    Wednesday, October 23, 2013 9:22 PM
  • Hello.

    Open an elevated cmd prompt

    Run diskpart

    then run list disk

    to get a list of all the disks , report if you see the object in question

    run list volumes

    Report if you see the object in question.

    Thanks, Darrell Gorter [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.

    Wednesday, October 23, 2013 11:13 PM
  • This site is incredibly frustrating as you can't attach any links or screenshots.  I even went back into my previous Microsoft account that I have had for over a year and it still says I can't post those until my account has been verified.  Ok, now we're past that. 

    Darrell, I ran the commands you mentioned.  List disk shows one disk, disk zero with a size of 460 GB, Free 1024 KB, nothing under the Dyn column and an asterisk under Gpt.

    Under List Volume I get 5 volumes.

    Volume 0, Ltr C, Label OS, FS NTFS, Type Partition, Size 438GB, Healthy Boot

    Volume 1, no drive letter, Label System, FS FAT32, Partition, 300MB Healthy System

    Volume 2, no letter, Recovery, NTFS, Partition, 600MB Healthy Hidden

    Volume 3, no letter, no label, NTFS, Partition, 350MB Healthy Hidden

    Volume 4, no letter, label Restore, NTFS, Partition, 20GB Healthy Hidden

    I also went further and selected disk zero and ran "list partition."  In this case there are now 6 partitions.  The extra one (listed partition 3) says the Type is Reserved and it is 128 MB.  So do I have 5 or 6 partitions, and why so many.  I can see the need for 4, System, Primary, Recovery and Restore. 

    Does anyone know what all these are?  Is one windows 8 Recovery and another 8.1 Recovery?  How can you tell which is which?

    Thursday, October 24, 2013 1:18 AM
  • Hello Davidoo,

    I did what you said and still the same. Same weird partition and still not able to optimize my whole HD.

    I have a hybrid HD but it's listed as a regular HD. I went to Dell web site and update all the drivers in hope that will fix it but no luck

    I think MS rushed win 8.1 and its still full with bugs.


    Thursday, October 24, 2013 3:07 AM
  • eSetter......Do you have a RAID setup that makes your drives appear as one drive?  You mention you have a hybrid HD, so I'm assuming that means one traditional hard drive and one solid state drive.  I'm not experienced enough with that to tell you if that can use the RAID configuration. 

    Also, did you go to the system folder Windows/Performance/WinSAT/datastore and delete the Disk_Assessment XML file?  Then did you run a Command Prompt as administrator and type winsat prepop?  At least for me, this made Windows 8.1 realize I had SSDs. 

    Thursday, October 24, 2013 4:32 AM
  • for those wanting to post a screenshot, I have put two up in this thread.

    strange partition

    Thursday, October 24, 2013 7:58 AM
  • Hi KIWIRJ,

    I have the same weird partition which needs optimization but on top of that I cannot optimize the whole drive.

    As for DAVIDOO1 question, No I did not delete the XML file but I'll try it again. I do not have RAID. The hybrid HD I have is one drive with part of it SSD and another part regular drive (kinda 2 in 1). That's not an exotic and they are in existence for a long time.

    Microsoft did a lousy job with Win 8.1! Shame!

    Thursday, October 24, 2013 12:39 PM
  • Davidoo, the 128MB partition is the MSR partition and it is a requirement in order to intall Windows in EFI mode.

    I have seen multiple threads where after the upgrade people have a new partition. I am to expect that it has installed a recovery partition that contains the Windows 8.1 WinRE. In my own testing I was not able to replicate this behaviour so I can't be certain. However seeing how many people have their systems installed in EFI mode, I should try this because I didn't do that last time.

    Regarding hybrid drives, to ease any confusion, they are seen by Windows as being a normal (spindle) drive. The SSD component is used by the drive's firmware itself and has no interaction with Windows itself.

    Thursday, October 24, 2013 3:39 PM
  • Hi Davidoo1

    It looks like strange drives been around since Win 7.

    Search in Google "unidentified drive \\.\Volume" There are couple of links about Unknown/Undefined volume

    Please let me know if you have any success.


    Thursday, October 24, 2013 6:04 PM
  • Hello,

    Yep that is the MSR volume and expected to be present on the system using GPT disks.  This is required for any GPT disk.

    Not sure why it shows with Disk Optimize however

    Thanks, Darrell Gorter [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.

    Thursday, October 24, 2013 6:27 PM
  • Here are the screenshots as I'm finally able to post them.  Not sure how I got so many partitions....

    Friday, October 25, 2013 3:46 AM
  • And here is a screenshot of all the partitions for disk 0.  I'm more of a hardware oriented tech person, so I admit to not being an expert about these partitions.  Can anyone tell me what all 6 of these showing are, and which ones I don't need? 

    I know that partition 1 is the EFI section, and an earlier post said that partition 3 with 128 MB was something necessary to install the OS.  Obviously partition 4 is the OS, drive C.  So, what are 2, 5 and 6?  One is probably the recovery for windows 8 and another for 8.1, but which ones?  That still leaves one more Recovery drive I have no idea what is for.  Can I delete them, and if so will I be able to expand the primary partition to take that unallocated space?  As I said, this is not my area of expertise. 

    Friday, October 25, 2013 4:02 AM
  • Partition 6 is likely where your recovery image is stored. It may be impossible to determine which of the 2 other Recovery partitions is the newer one without fiddling with Diskpart. If a (human) error were to occur, it may make your recover ability inoperable. Ideally, one would work with this PC outside of Windows and from a WinPE instead.

    Then again, we're only talking about either 350 or 600MB here, a size small enough to maybe not even bother.

    The real question here is why or what is causing the new partitions to appear and what are they for? The best way to figure this out would be to replicate the behaviour on some test systems and not using someone's regular computer. That way we can "Screw up" and not worry about losing data. I just finished my EFI deployment of Windows 8 and about to do the Windows 8.1 Update to see if I can replicate this.

    But if you want to go ahead and delete one of these partitions (you'll notice Disk Management won't let you) the answer to that particular question was posted here:

    • Edited by Tripredacus Friday, October 25, 2013 2:56 PM
    Friday, October 25, 2013 2:56 PM
  • Hello Davidoo1,

    I spent lots of time educating myself and here is what I found:

    1) That strange name on the volume like \\?\Volume{GUID}\  is actually the name of the volume.

    You can read more about that here:

    2) Put in the Run box the name of your volume. In mine case, after I put the name in Run box and hit enter, it opened windows explorer window and there were recovery files from the upgrade.

    Obviously Microsoft didn't do a good job with the upgrade of Win 8.1 (at least in my case).

    Also you can run from Command Prompt mountvol and see all the volumes you have on your PC. Since Win 2000 there is big change of the "volume" and "partition" concept.

    In my case I do not know what to with that recovery partition which I cant optimize and on top of that interferes with the optimization on whole drive.

    I'm an engineer by trade and feel like I'm wasting my time dealing with the lousy job Microsoft did, trying to fix my own computer after installing their shitty upgrade so soon!

    Good luck!

    • Proposed as answer by QUIX4U Monday, December 09, 2013 2:23 AM
    Friday, October 25, 2013 11:38 PM
  • Ok, I went ahead and created a recovery disk on a USB drive and afterwards the system asked me if I wanted to delete the recovery partition on the hard drive.  I said yes, and this turned over 20GB to unallocated space on partition 6.  I then went into Diskpart and deleted partition 5 of 350MB.  Not really sure what it was, but not too worried as I have the recovery on a USB stick now anyway.  Next, used Disk Management to spread the Primary drive C to the right to take up the unallocated nearly 21GB.  So, the result is now only 3 real partitions and about 21GB more on drive C.  Still not sure what is on the recovery partition 2.  Could be the original Windows 8.  I had never done this before and it scared the shiite out of me keeping my fingers crossed on the restart, but all ended up fine.  Computer seems snappier now, but could all be in my head.  Thanks to Tripredacus for the insight on using Diskpart along with other advice.  I still don't think this has been answered as the original question as to why the Windows 8.1 setup is creating new partitions has not been explained.

    Here's the Diskpart screen before.....

    And here's the Diskpart screen after.....

    • Edited by Davidoo1 Saturday, October 26, 2013 4:34 AM
    Saturday, October 26, 2013 4:21 AM
  • And here is the "old" Disk Management allocation, followed by the new "cleaner" version.

    Saturday, October 26, 2013 4:27 AM
  • Are you sure the 20GB recovery partition was actually empty? Disk Management will show a 100% free space if the contents are marked with System and Hidden attributes. I suspect you had your recovery image in there...

    For example, Partition 1 which shows 300MB and 100% free is not the case. There should be aat least 203MB worth of files inside.

    Also as a side note, I have found that the Windows 8.1 update from the Windows Store will create a 350MB Recovery partition after the OS on a GPT disk, but not on an MBR disk.

    • Edited by Tripredacus Monday, October 28, 2013 5:16 PM
    Monday, October 28, 2013 5:16 PM
  • The 20GB recovery partition did have data in it as I copied that recovery drive to a USB stick.  Once I did that the system gave me the option to delete this drive, which is what I did so I could then expand the C drive into that space.  It was definitely not empty because I can see the recovery on my USB stick now.
    Monday, October 28, 2013 6:34 PM
  • I got the same mysterious new volume in my C:

    It starts with \\?\Volume{ ....

    On top of that it shows its heavily fragmented but Disk Optimization cannot fix it.

    Exactly the same extention hard drive added here in New Zealand.. on TWO identical Acer Aspire Z3-605's purchased NEW from a retail outlet.

    NEITHER have any flash drive or OTHER peripherals attached.
    BUT -- within a few days of initial SWITCH-ON .. both had a NON_OPTIONAL upgrade to 8.1 enforced on them.
    Now both have a 23% fragmented NEW hard drive entitled as:


    But neither can be OPTIMISED (as it 'flashes" running and then does ABSOLUTELY NOTHING.
    The HARD DRIVE named as:


    Simply resists ALL ATEMPTS to defrag it.!!!

    AND --IT IS NOW CAUSING MY NEW (read that as 2% of 1TB HARD DISC memory used) Hi-Capacity Hard Drive PC..
    To fail..
    AND TELLS ME (it has done this several times now with a pop-up alerts box)


    Yet the dam thing keeps crashing & alerting me to an OUT OF MEMORY fault.!!!

    (Oh & p.s.. this website REFUSES to allow "screenshots" to be added into comments - thus denying everyone the "right" to ask for help.!!!) 

    Monday, December 09, 2013 1:36 AM
  • Hello Davidoo,

    I did what you said and still the same. Same weird partition and still not able to optimize my whole HD.

    I have a hybrid HD but it's listed as a regular HD. I went to Dell web site and update all the drivers in hope that will fix it but no luck

    I think MS rushed win 8.1 and its still full with bugs.



    (What amounts to an almost 4kn useles M/S O/S 8.1 NEW PC!!!)

    I still rely on my almost bullet proof (2006) XP machine.
    As that is the ONLY that one I have which still "supports" NZ Telecom's Extra ISP POP email.
    As the so-called brilliant (but isn't) 8.1 system - ?


    Monday, December 09, 2013 1:47 AM
  • Hello,

    Yep that is the MSR volume and expected to be present on the system using GPT disks.  This is required for any GPT disk.

    Not sure why it shows with Disk Optimize however

    Thanks, Darrell Gorter [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.

    Well that explains it all then .. doesn't it.

    Is deliberately 4kn with everyone's BRND NEW PC's.. Because they 'have been told" that their very efficient easy to use ..
    XP machines.. willNOT be supported after Feb 2014 ..

    With this useless win 8.1 system

    Well - Apple sure does LOOK good .. from a (totally disgusted with your useless operating system)
    Forced to BUY new PC's with Win 8 that autiomaticly enforces users to UPGRADE (without an opt-out) Such that you NOW have several thousand (going on several million) EXTREMELY IRRATE customer's "points of view" - regarding MS's shameful;l enforcement - into win 8.1 for all of it's previously HAPPY clients. now.!!!

    Monday, December 09, 2013 2:19 AM
  • I have the same, after browsing the web, I think the answer is this is your SSD as others have said that        

     Win 8/8.1 mislabels this as hard disk.  Advice from Microsoft and others is SSD should not be defraged(trimmed) although it is possible to change the labeling and defrag.  I'm leaving mine as it is unless my computer slows down, then I will have to research again. Microsoft should address this issue at least in a text explanation if not also a corrective patch.

    Sunday, December 29, 2013 7:31 PM
  • the solution is very simple if you are using dell then go to my dell utility and run pc check up and then drive space manager and scan the drive other drives will not seen after this....

    Wednesday, February 05, 2014 3:35 PM
  • I am afraid you are all wrong expect davidoo1 you will have to delete partition 5 to get rid of the strange drive in windows 8.1. To do that open up command prompt as administrator and do the commands I write



    list disk

    select disk 0

    list partition

    select partition 5 note it should have 450mb or 20mb depending on your system.

    delete partition override

    then it should be gone to check go to defragment and optimize your drivers and it will not be there

    note David001 you should not have deleted partition 6 it was a recovery partition it will recover your system if you have a problem. There is no need there should be only 5 partitions not 4 but at least you copied the files before deleting the partition.

    Note after restarting the computer partition 5 will be back but don't worry it just changed the number and moved the recovery partition just leave it. The strange partition is gone for good and will not come back well only if you go back to windows 8 and update to windows 8.1.

    Tuesday, March 25, 2014 9:20 PM