Why did I just get an ‘Unrecoverable processor error’ – and what does it mean?

Every now and then a user will report seeing an unrecoverable processor error under Virtual PC – and wonder what the heck is going on and what it means.  Virtual PC will display this error message when one of two events happen:

  1. When something happened that would have caused a physical computer to spontaneously reset.

    On a physical machine – there are a number of things that you can do that will not only cause the operating system to crash, but will cause the entire system to spontaneously reboot.  Needless to say these are usually fairly drastic problems – like have the wrong hardware abstraction layer driver loaded.  On Virtual PC – rather than simply rebooting we provide a relatively meaningless dialog…  Hmm…  Maybe we should try and add some more detail to the dialog message.
  2. A problem was encountered in core emulation.

    This is thankfully very uncommon – but sometimes there may be a low level CPU operation that either is not supported by Virtual PC, or is only partially supported under Virtual PC – and using this operation may cause an unrecoverable processor error.

Either way – when you see this error message your only option is to reset the virtual machine and try to reconfigure it to avoid the problem.