When migrating a physical computer to a virtual machine - there are a number of potential problems to be aware of.  However, it should be noted that these are the exact same problems that are encountered when migrating a system from one physical computer to another.

There are a number of tools available today from Microsoft and other software vendors that will allow you to automate this process (http://www.microsoft.com/windowsserversystem/virtualserver/evaluation/vsmt.mspx, http://www.platespin.com/Products/PowerP2V_Virtual_Server.aspx) - however - in the case of a 'one or two system' desktop migration, these tools really are overkill.  This series of posts is going to focus on migrating Windows systems - but there are similar issues with migration of most other operating systems.

Problem 1: "STOP:0x000007B Inaccessible Boot Device"

You image the physical computer to a virtual machine - and now when you boot it blue screens almost immediately with a "STOP:0x000007B Inaccessible Boot Device" message.  What is going on?  Well, Windows maintains a list of 'critical boot devices' that are loaded in order to boot the system.  One of these devices is going to be the hard disk controller that you boot the system off of.  Sometimes - your physical computer will be close enough to the virtual machine that you do not see this error message.  However - if you do see this problem - you will need to do the following:

1. Go back to the original physical computer
2. Boot Windows
3. Go to 'Start' --> 'Control Panel' --> 'Administrative Tools' --> 'Computer Management' --> 'Device Manager'
4. Expand the 'IDE ATA/ATAPI controllers selection'
5. Double click the 'controller' entry (not the 'Channel' entries)
6. Go to the 'Driver' tab
7. Select 'Update Driver'
8. Select to 'Install from a list or specific location (advanced)'
9. Select 'Don't search. I will choose the driver to install'
10. This should display a list with your specific controller and a Standard / generic controller.  Select the standard / generic controller.
11. Finish the wizard
12. Shutdown the system
13. Attempt to migrate the system again

This is the only problem that I am going to discuss in this series that requires you to make a change to the physical system before you migrate it - but thankfully it is a non-destructive change - as you will still be able to boot the physical system with no problems after this change.

Cheers,
Ben