I am a big fan of developing on virtual machines. This gives me freedom on which VM I am working on (based on current project) and also possibility to ease backup and restore. VMs also give me environment which is closer to client environments as I am using Windows Server as OS and other nice features. Using VMs is also great form of avoiding problems with lots of Sitecore instances on one machine and filling in memory, CPU, and so on with lots of processes.

I am using Oracle VirtualBox instead of Microsoft Hyper-V as it has more features for me currently.

I am usually just copying VMs through Windows Explorer to create a new project / VM and then the VMs have the same UUID.

This causes trouble as you cannot attach another VM with same UUID as they are colliding.

You will get this kind of exception in Oracle VirtualBox when you try to add another VM with same UUID:

Cannot register the hard disk ‘C:\_VMs\SC9u2\sc9u2.vdi’ {ca2bdc6a-a487-4e57-9fcd-509d0c31d86d} because a hard disk ‘C:\_VMs\SC9u2\sc9u1.vdi’ with UUID {ca2bdc6a-a487-4e57-9fcd-509d0c31d86d} already exists.

There is however easy way how to avoid and fix this.

Follow these steps (note to my future self :-)):

  1. Open Command Prompt and navigate to folder where you have installed Oracle Virtual Box. For me it was “C:\Program Files\Oracle\VirtualBox”
  2. Type in this command (put path to VM which you would like to change UUID between “” ) : 
    VBoxManage internalcommands sethduuid "C:\_VMs\SC9u1\sc9u1.vdi"
  3. Message appears on your screen -> UUID changed to: 2092c763-22e6-4617-970a-4cdb56e7743c
  4. Done!

Happy virtualization!