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Tuesday, 9 November 2010

How to fix the 'Cannot mount the backup' problem in WHS

Regular readers will know that I'm an ardent fan and user of Windows Home Server (WHS). Last year I built my own system to look after my three PCs, a job that it's done admirably, despite a couple of failed drives (note: never put ancient drives in USB enclosures, it's a false economy!).

But the other day I decided to check some old versions of files using WHS's file and folder restore facility, which temporarily loads a backup set as a Windows volume. The progress window on the WHS console got to 100%, but on the Windows 7 client window it always stopped at 81% before popping up an error message saying 'Cannot mount the backup'. This was very frustrating, as mounting the backups worked fine on my other two PCs, so it obviously wasn't a WHS issue.

WHS can mount backed up partitions as Windows volumes. Sometimes.

Looking around the various WHS forums, I found several suggestions for a fix, none of which worked. Eventually, a post on the We Got Served forums led me to a thread on the Microsoft forums which mentioned a problem with Diskpart. I tried this and it worked first time, although I've no idea why automount was disabled in the first place.

Here's the fix:

  1. Right-click the Command Prompt icon and choose 'Run as administrator'. (Command Prompt is located in All Programs, Accessories).
  2. Type 'diskpart'. After a couple of seconds the prompt will change to 'DISKPART >'.
  3. Type 'automount enable' and press Enter. You should see a confirmation message.
  4. Type 'exit' to quit Diskpart and 'exit' again to quit the command prompt.



Try mounting the backup partition again via the WHS console and it should now work. It seems as though there may be multiple causes for this behaviour, so I'm not guaranteeing it will work for everyone.

Update  20/11/2011: To those who are worried that this problem means that the backups themselves are corrupted, don't panic - the problem is caused by the client PC, not the WHS backups. The backups are perfectly safe and you should still be able to perform a full system restore from the backups, using the WHS client restore disc. The problem discussed here only affects the ability to restore individual files and folders.

Another thing to check if this fix doesn't work is to make sure that nothing is using the Z: drive. In Explorer, click Tools, Disconnect Network Drive. Highlight anything using the Z: drive and click OK. You can also do this from the command line. Type 'net use' to see a list of drive mappings. If Z: is in use, remove it by typing 'net use Z: /delete'. This won't delete data from any drive, it just removes the drive mapping.

43 comments:

  1. It didn't work for me. I got a window telling me I needed to format the X: drive before I can use it. Then I get the cannot mount error.

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  2. I've got years of our twins events, observation notes, pictures, etc., supposedly backed up to WHS - and it seems I have no access to my backups due to this same issue. My wife is nearly hysterical, and i'm not a happy camper either. Is there a way to retreive the backups directly from the WHS via a remote access session maybe?

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  3. ps. my results are the same as noted by Klaus

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  4. Hi Dave - sorry to hear the fix doesn't work. It seems there are a lot of other users in the same boat, so there must be more than one cause. It seems to be related to a particular PC, so if you have another PC, try joining it to WHS and opening the backups from there (you can't do it via remote access).

    One other cause seems to be if any application is using the Z: drive letter for any purpose - this is the drive letter WHS uses to mount the backups (pretty stupid - why didn't MS use the last available drive letter rather than hard code it to Z:?).

    The backups should still be usable via the PC Restore CD (if not, then your backups have become damaged somehow), so they're not completely 'lost' - you could restore a backup to, say, an external USB drive if you just wanted to get access to personal files.

    Hope this helps.

    Kelvyn

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  5. Kelvyn,

    Thanks for the post. This resolved my issues. I'm using a Window 7 x64 client with WHS PP3 and until I enabled automount, I could never see the backup.

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  6. Thank you so much for this. I had the same problem where it would stop at 81%. I searched all over the net then came across your blog, did what you suggested and voilà! I have access to a backup for a drive that got wiped.

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  7. I have 8 PC's. XP pro, Vista, Win7. I have had WHS backup running for the past 2 years. I was able to get to any backup from any computer until recently. When I say recently I say this because I have not tried until this week.

    None of my backups can be opened from any computer, this is my error.

    Search the web and you will find that no one has solved this issue. MS had a winner with WHS, now it's a loser.

    WHS just became worthless in my mind. I have been an advocate for WHS just for this one reason. I thought I was safe.

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  8. I got hit with this problem several months ago. I was checking the web again tonight for any "new fixes" because I have tried all of the old fixes with no success. It's almost criminal that Microsoft is still shipping this product. Just when you need your backup most, and you've been told time and time again that your most recent backup was successful, you can't get to one copy in any way. I have tried 5 different computers with all kinds of different OS to no avail.

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  9. This solution worked for me like a charm. I had just installed Virtual Drive Clone before attempting to mount a backup - that may or may not have been the cause of my problem.

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  10. I was unable to mount any of my backups after upgrading to Win7 Ultimate and this fix worked for me. Was not a problem on Win7 HomePremium though.

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  11. This did the trick for me as well, thanks! I was accessing via WHS client running on my new Windows 7 Pro 64-bit system, which is not the system that had been backed up (Windows 7 Ultimate 32-bit). I recently installed a NAS-type drive, "Seagate GoFlex Home", which got mapped to network drive 'Z'. Anyway, the diskpart automount enable did the trick. The backup image then automatically mounted as drive 'I', so I was able to copy files to the new system.

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  12. thank you! worked for me on windows 7 64-bit where automount was disabled (by default?)

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  13. Thank you much! Worked for me on Win7 Pro 64bit. I had another Win7 Pro PC that could open the backups, but one that couldn't (plus an XP PRO that worked as well). Lots of searching, then finally your Diskpart solution. I'm wondering what turns Automount off since I had one Win7 Pro working and one not working... I wish I could trace down the culprit software that disabled Automount. Any ideas? Did you ever figure out what turned your's off Kelvyn?

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  14. You're welcome! No, I'm not sure what turned off automount, as the system default is 'enabled', although given that I test an awful lot of software and hardware on my PC, it could have been something that has long gone.

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  15. I have 3 PCs runing XP Pro.

    Not a one can open a backup today. Same error. Admittedly I have not tried to open a backup in months and I was running along feeling safe and secure just like the people who know nothing.

    Now if what everyone says is true, I am livid. The hole purpose for the WHS for me was seamless automatic backup.

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  16. Did not work on WHS with a XP Pro PC (Tried it on 3).

    Consistently fails at Open 75%.

    This really has destroyed my confidence. Fortunately, if I lose what I was trying to recover today, not a big deal. BUT what if my whole drive had crashed???

    That is why I have a separate box with WHS.

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  17. THANK-YOU, THANK-YOU, THANK-YOU, THANK-YOU!!

    Your mini guide completely solved the exact same issue i had with a Win7Ultimate machine.

    Kelvyn, your both a gentleman and a scholar :-).
    Oh and....Thank you, again.

    Chris.

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  18. Bummer. It didn't work here :-(

    Appreciate you posting anyway.

    This is not a good situation and I'm biting my lip to stop me saying other things. %$#@!

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  19. Bingo! Windows 7, 64-bt for me as well. Thanks for the tip, I am so glad not to have a WHS full of unusable backups!

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  20. Beautiful!
    Thank you so much for this tip!
    Worked for me on Vista Ultimate 32-bit.
    Steve

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  21. No luck for me. I have an XP-MCE 2005 box who's hard drive just crashed. after replacing with exactly the same drive I am unable to restore. From my 64bit Win7 laptop I cannot even open the backups - automount is on - Z: is free. nada.

    what a waste. :(

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  22. Anyone have another solution to the failure of WHS backups to "mount"? My server has been running great since the early days, updating, and permitting access to files when needed. Now, with W98, W7, and Vista on line, NO platform will mount. All of that supposed security is down the drain. The 'automount enable' suggestion does not work on any. The silence is deafening. Has MS given up on WHS? Is WHS2 having the same problem?

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  23. WORKED FOR ME

    Thanks a bunch

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  24. Thank you! I've been rebuilding my Windows 8 system and it seemed like nothing was going right (I've been scouring the internet for troubleshooting hints all day).

    I had this problem, and your site was the second one that I looked at and BOOM! Fixed. THANK YOU for posting this.

    BTW, everything is going *right* now. :)

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  25. Kelvyn -

    I'm SO discouraged! I've done all the above and STILL nothing works. I have some critical files I need to get ASAP and I'm not able to restore since having the 81% WHS issue. Any other suggestions???

    Thanks!!!

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  26. I tried this and it didn't work. I have windows 7 64 bit in case that is relevant. What worked for me was to disable the Home Server Restore driver under the systems folder in device manager. Voila I could open the backup and view files.

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  27. Hi, Vista Ultimate 64 bits. I also got it to work by disabling the Home Server Restor driver.

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  28. Kelvyns proceedure worked for me. I followed the instructions and the backup passed 81% and got the errorr message at 91%. Decided to restart the computer and it now worked perfectly. Theank you.

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    Replies
    1. You're very welcome, glad it worked!

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    2. Hi Kelvyn, Please I have a HP Media Home Smart Server running WHS with successful backups for the past 3 years. However just last week I lost my files on my personal pc which runs Windows Ultimate and tried to restore from the server. But I got the error message "Cannot Mount Backup" "Backup Services not Running". I get these error messages sometimes with restoration at 49% and mostly at 81%. I have tried all solutions including the enable auto mount but still no solution. Microsoft cannot support me and HP will not support me either, Please can you help?

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  29. It worked for me using the steps as described.

    Thanks alot.

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  30. I am running Win 7 x64bit SP1 and the 'enable automount' did not correct the "Cannot run AutoMount.exe" problem. I eventually did a "Repair" on the "Window Home Server Connector" software in the "Uninstall program" within "Control Panel".

    As additional background . . . the hardware is a HP WHS Ex495 version 3.3.1.35433. Since June 2nd 2013, I have had problems with performing multi-partition backups. The server would complete the first partition and then hang. A power off was required of the WHS. If the server was restarted, the first and only first backup partition would run to completion. Failing there after. Why a power-off and then power-on would not correct the problem really baffles me. From my 38+ years of non-MS Windows System/Network Engineering, this tells me this may be a multi-variable issue. And, that I may not have it completely resolved yet.

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    Replies
    1. Thanks for everyone perspective on these WHS issues. I should of read the part about the Z: drive closer because this coincides with my June 2nd 2013 issue. While performing this weekends backups for the 4 laptops, I discovered yet another workaround to correct hung backup clients for my "Windows Home Server Connector" software. The "Wake Server" option has twice resolved a HUNG backup client.

      --Mark

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    2. Thanks for the instructions everyone.

      What worked for me:
      1) automount scrub
      2) automount enable
      3) did a "Repair" on the "Window Home Server Connector" software in the "Uninstall program" within "Control Panel".

      Thanks again!

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  31. Thanks so very much for the fix. The "Z" drive solution is what fixed it for me.

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  32. Having the same issue on WHS 2011 on two clients. Nothing has worked. I do have a third client that I can restore files to along with a VB running Windows 10 preview. Can some one help with the wake server comment above.

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  33. I have several computers back-up with WHS. I can restore all but one, so most of what is suggested in this thread does not apply. Any suggestions would be appreciated.

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  34. I have several computers backed-up with WHS. I can restore all but one, so most of the suggestions in this thread do not apply. Any suggestions would be appreciated.

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  35. I now have the 81% issue and tried everything including a Restore of the WHS. Still no luck and a SO who is about to divorce me. It may be time to move on from WHS.

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  36. I experienced this problem from Windows 8.1 desktop. I removed a Z: Network drive and that did not work. I then did the 'automount enable' in diskpart and that fixed the 'Cannot mount the backup' problem with my HP ex495 WHS 2003 server. I did notice that it mounted the recovery image as Z: drive, so I probably needed to perform both steps. Thanks for documenting this problem and solutions!

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  37. I encountered the problem after recovering from a drive crash. I had to run the "clean up now" function under backups on the server as well as execute the auto mount scrub function on the client. I also reinstalled the connector software in the process of trying to fix this. Seems to be working consistently on all my machines now.

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  38. I know this is late to the party but thru device manager, with WHS 1 console open to view a backup, delete the WHS restore drivers (I had several) except try updating the last one. Reboot. That worked for me. Using Windows 10 and WHS 1 (but not much longer).

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  39. Running WHS 2011 on windows 7 pro client. Had this issue on several clients. All of a sudden they started working. Now they are back to not restoring files. I do I have two other client machines that are still working with the file restore. I have tried the above solutions with no luck. I did read a not about wake the server. What is that? Any new updates or things to try would be great.

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