Ali Moeen’s Blog

When a Windows 2003/XP virtual machine is migrated to Hyper-V, it is not easy to migrate it back to Virtual PC – or VirtualBox. The reason is Hyper-V changes HAL and it is not easy to change the HAL on 2003/XP machine. This issue is solved since windows Vista and up. Starting windows vista, Windows can detect and change HAL. The detect and change HAL option is available in MSConfig->Boot Tab->Advanced Options->Detect HAL

Windows 2008 guest has built in support for Hyper-V; however, when a Windows 2008 image is migrated to Hyper-V, “Detect HAL” option should be selected or Hyper-V drivers won’t work. The following screenshot shows the symptoms of undetected HAL in a windows 2008 guest: