Windows Home Server Cannot Even Mount Backups


Windows Home Server has had it’s fair share of?embarrassing?issues that really shouldn’t happen to a server. First of all, it didn’t really support the sort of home power users who were buying it, because it didn’t support backing up 64bit systems for the first year after launch. Secondly, it was corrupting files (I personally lost a few photos to that when they were corrupted while rotating them). Thirdly, until recently you couldn’t back up the server itself, so it was a fairly lousy place to store files.

Now a new issue is becoming more common, which is the inability to recover backups. More and more users are reporting that when trying to mount a backup, the process gets to 81% and then gives the error “Cannot mount the backup”. This was meant to be resolved with Power Pack 3, but from personal experience, I can tell you that it is not, even in the final version. To make matters worse, the symptoms are that you can mount a backup once on each client machine, and then never again. So you get the false sense of security that everything is working fine if you check the backups, but it fails as soon as you really need it.

The key thing about the “81%” part of the issue is that this is the percentage that you get to when WHS has built it’s own internal image of the drive as of a certain date and is then about to mount the drive for you. An error at this stage means that the system is basically unable to mount the drive for whatever reason. There are lots of potential reasons for this, such as having a drive already mounted to “Z:”, or having not enough disk space on your system drive on the server, or needing to rebuild your server database.

Unfortunately though for many users, the issue is not that simple. There are lots of feedback issues logged on Connect for this issue, so it’s hitting lots of people. Some have said it is restricted to Windows 7 RC1 too, but I personally have seen the issue on Vista Ultimate 64 bit, Vista Premium 32bit, Windows 7 RC1 and Windows 7 RTM, so I don’t believe it’s just an OS specific issue. At the moment there seems to be no solution in sight.

Update: Last week I tried to do a complete restore of my Media Center, which had got corrupted somehow. It was a complete disaster – it ran for 2 hours then wouldn’t reboot (no boot sector on the hard drive). After several runs through with the System Repair disk, I got it to boot, but it was not a proper restore – my user profile wouldn’t work, and nor would most of the applications. In the end I just did a clean install. Very?disappointed?in that too. Thank goodness I keep my media on a different partition to my OS.

So, as far as I am concerned, I think that Windows Home Server has failed in the key tasks that it was meant to do. It didn’t store files without corrupting them (fixed now admittedly), and it doesn’t allow you to restore either files or complete partitions. A basic NAS would do a better job. Anyone got any suggestions for a simple alternative OS to put on an HP EX-475 to turn it in to a working dedicated server?

Update 2: I have a solution (kind of). Since none of the backups would restore, there was no point having them, and because of the problem, I wasn’t getting any new backups. So, I decided to delete my entire backup directory and start from scratch. Steps to do this were;

1) Go in to Home Server and remove every computer from the Backup tab.

2) Uninstall the home server connector from all PCs

3) Open?a Remote Desktop Connection session to your home server.

Open a Command Prompt, Click Start, Run and type CMD
Type net stop PDL.
Type net stop WHSBackup
Delete the contents of D:\folders\{00008086-058D-4C89-AB57-A7F909A47AB4}. ?Do not delete the folder.
Type net start WHSBackup
Type net start PDL.
4) Reinstall the home server connector on all PCs and configure the backups. You will have lost all of your old backups, but at least new ones will be recoverable.


10 Responses to “Windows Home Server Cannot Even Mount Backups”

  1. JerryC says:

    I had the same problem with Vista Ultimate 32bit & 64bit, windows 7 utilmate 64bit RC & RTM.

    While I only had it stall once at around 80% , I was conistently having problems at 6% when it could not moutn the backup. Did not have any problems on XP MCE 2005 (32bit)

    I found that reinstalling the connector fixed the problem in all instances. The problem did return once in win 7, I’m not sure what updates were applied that caused this problem.

  2. David says:

    I also have a problem with it freezing at 6% and then saying it cannot mount. I have tried re-installing the client software.

    What I really want is to be able to mount a backup from the server itself, but it gives the message you have to do this from the client machine. Why?!


  3. I wish I could help. It would indeed be good to be able to mount the backups on the server – bizare that you can’t.

    I tried to do a complete restore last week too, and that also failed. So as far as I am concerned, WHS is a complete fail.

  4. Peter Wood says:

    I too have the problem. I am on Windows 7 RTM 1 and I cannnot even load one file from any backup. This is rubbish. its so complicated and my whole backup strategy for 4 PC in the house has been based around this. Its worse than poor.

    How do I recover my backups?

  5. Laura says:

    I found that reinstalling the connector fixed the problem in all instances. The problem did return once in win 7, I?m not sure what updates were applied that caused this problem.

  6. Dave M says:

    Windows XP Pro 32 bit. Same problem. Re-installing the connecter did NOT work for me. I have over 1 and a half years of backups on this box that I am unable to use. What an epic fail. I can’t believe that once again I wasted my time and money on a Microsoft product that doesn’t do what it’s advertised as doing. I mean…really. What is it for? Backing up! of course! Does it backs up your data every day! What if I need those backups..can I restore all my data? Thank goodness I’ve been backing up religiously for almost 2 years! Well…er….no. you can’t restore. Um… oopsie! Sorry! Oh well…um….just unistall and re-install and start all over!!! Well…in another 2 years when I need to restore something…will I be able to?…most likely not!

    Come on man!!!

  7. Marty Evans says:

    Can’t get access to backups either from a Vista or Win 7 client. Spent three hours on phone with HP Media Server guys. I get the identical “cannot mount” message and 81% stall as above. We also tried running mountvol /E at the cmd line as admin. Not sure where this one came from, but that is one of the trees HP is running. Updated to PP3. Could it be that the original backup was PP2, that there are issues with database across the updates? Hmmm. Sure wish HP or MSFT would post a troubleshooting tree with all the tricks. Could be a combo that would work for most.

    One of my client drives failed this week. All our photos since we went digital in 1999 (200GB). My wife has been crying. Kinda sad, and you can imagine I am a little stressed. I am gonna try the hard drive angle using a data recovery tool next.

    I can tell you this, I will never again trust a backup server and will be back to manual weekly backups.

  8. Chuck says:

    This worked, used the first recommendation on the list.

    Log on as the administrator who installed Windows Home Server Connector.
    Exit Windows Home Server Console.

    Click Start, click Run, type cmd, and then click OK.
    At the command prompt, type the following command, and then press ENTER:

    cacls “%allusersprofile%\Application Data\Microsoft\Crypto\RSA\MachineKeys\*” /C /E /G Administrators:F

    Exit the command prompt, and then log on the computer by using the administrator account that you want to use to restore the backed up files.

  9. Regarding the “Update 2: I have a solution (kind of)” post, I want to thank you. I have been fighting this format drive and unable to mount message issue for many days after reinstalling my WHS after a hardware change. Luckily I too did not need the backups, just needed to restore new ones and this solved the problem. I did attempt to bring over the DAT files from the previous build so bring over the backup data where some may had been corrupt. After applying all windows updates, I was finally able to see them later but my monkeying with trying to view them before the applied updates may have caused all these drive mount issues. Thank you!

  10. Johan Lindh says:

    I was able to mount and restore by disableing the Home Server Restore driver under the systems folder in device manager. Found the tip on

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