UUID mismatch when launching VM #45

kschults opened this Issue Nov 9, 2011 · 17 comments


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kschults commented Nov 9, 2011

When I try to open any of the installed VMs, I get the following error:

Failed to open a session for the virtual machine IE7.

UUID {5a5e730b-42e1-8b48-90c0-c1b9248e1722} of the medium '.../.ievms/vhd/IE7/Windows Vista.vhd' does not match the value {3097458d-2ebe-4560-8b8f-3e6d73780a6e} stored in the media registry ('.../Library/VirtualBox/VirtualBox.xml').

Result Code: NS_ERROR_FAILURE (0x80004005)
Component: Medium
Interface: IMedium {53f9cc0c-e0fd-40a5-a404-a7a5272082cd}







ademaro commented May 23, 2012


xdissent commented Jun 1, 2012

Is anyone still seeing this? I tried typing +1 into my terminal but still have no idea how to replicate this issue. ;-)


Can't reproduce...

Such errors happen when trying to move the vhd files from one place to another.
On a fresh install of ievms I don't know how this error could happen.
Will try to check this and let you know if I find something ;)

suan commented Jun 2, 2012

+1, happened after VirtualBox upgrade

suan commented Jun 2, 2012

This worked for me. It involves manually editing your VirtualBox XML files, so be careful! Assuming the "IE6" VM is giving you trouble...

First, delete the VM, removing all data for it, and reinstall it via the ievms instructions (this step might not be necessary)

Then, in ~/VirtualBox VMs/IE6/IE6.vbox, make sure the disk exists in the MediaRegistry section, something like this:

        <HardDisk uuid="{20ddefcf-a24d-4659-b9a4-afc01770e548}" location="/Users/syeo/.ievms/vhd/IE6/Windows XP.vhd" format="VHD" type="Normal"/>

Also make sure that the disk is in the StorageController/AttachedDevice section, with a matching UUID, like this:

      <StorageController name="IDE Controller" type="PIIX4" PortCount="2" useHostIOCache="true" Bootable="true">
        <AttachedDevice type="HardDisk" port="0" device="0">
          <Image uuid="{20ddefcf-a24d-4659-b9a4-afc01770e548}"/>

Next, open your ~/Library/VirtualBox/VirtualBox.xml file and make sure the MediaRegistry section has the disk, like this:

        <HardDisk uuid="{20ddefcf-a24d-4659-b9a4-afc01770e548}" location="/Users/syeo/.ievms/vhd/IE6/Windows XP.vhd" format="VHD" type="Normal">

You should now be able to boot the VM!


@suan 's workaround makes a lot of sense, but it didn't work for me

kmendes commented Sep 12, 2012

+1 for IE7


If you delete the VM from within the Virtualbox GUI and remove all data, re-running the ievms installer doesn't fix the issue? When it creates the VM it assigns a new random UUID to the vhd, so there should never be any conflict. Somehow Virtualbox media manager got out of sync, but removing and reinstall should fix as far as I can tell.

Can anyone just try that and let me know what happens?


^ resolved the issue for me but it did require a reboot beforehand, nothing would make it work otherwise.


+1 IE7


I solved the issue by removing the vm and all files. I than run the install script again, which extracted the vhd and reset the uuid.


I had the same issue with another VM, and the following steps worked for me:

  1. Open VirtualBox (Oracle VM VirtualBox Manager)
  2. From the menu bar go to File > Virtual Media Manager (Ctrl-D or Command-D)
  3. In "Hard Drives" tab you will see all the virtual hard drives you have, and the messed HDs will have a stop like icon
  4. Right click your messed HD and click "Remove" (or Select + Delete key)
  5. From your file manager (Finder or Windows Explorer) go to the folder of your virtual machine, and drag-and-drop your hard disk to the "Virtual Media Manager" window.
  6. Close "Virtual Media Manager" window
  7. Go to your VM with the problem, remove and add again the vhd file that had the UUID mismatch problem

Here you go!

@xdissent xdissent closed this Feb 1, 2013

In case it helps someone out there, I was not able to follow step 5 from the above so I ended up clicking "Copy" and copying the "messed up" VDI - then VirtualBox was able to recognize it and I was able to carry on with steps 6 and 7.

huttarl commented Feb 17, 2016

In case it helps someone...

I had the above problem after restarting a Windows 8.1 VM. To solve it, I edited the .smdk file mentioned in the error message as "the medium", and changed the UUID that the error message mentioned there to the UUID stored in the media registry (which, again, I got from the error message).

Disclaimer: I have very little idea what's going on here; it just seemed like a reasonable thing to try, and it seems to have worked (for now).

Can I just say, this has been an extremely helpful error message? It tells you exactly what was supposed to match what, what both of their actual values were, and where to find them! So instead of taking in-depth knowledge of VirtualBox to fix the problem, a noob like me was able to do it.

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