How to disable time synchronisation under Virtual PC 2007

One of the benefits of the Virtual Machine Additions for Virtual PC is that the time is automatically synchronised with the host machine. In most cases this is desirable, but I ran into a case recently where I needed to test something using an earlier date, and not realising this I wrestled with the time settings of the guest OS to no avail – it just kept resetting to the current time!

The process for disabling this feature (on an image-by-image basis) requires editing the VMC file and is detailed at Ben Armstrong’s blog.

How to resolve “Virtual PC has detected an invalid or missing Product ID”

I’ve just installed Virtual PC 2007 on my work laptop (which runs Windows XP), and when I tried to start it, I got the following error:

Virtual PC
Virtual PC has detected an invalid or missing Product ID.

A valid Product ID is required to operate Virtual PC. Please
re-run the Virtual PC installer and enter a valid Product ID when

The solution is basically as described here, except I had to create the registry keys and values as they were missing on my machine.