The update KB959596 fixes two problems in P2V:
"Error (3133) Virtual Machine Manager could not connect to source computer servername.domainname.com after it restarted into Windows PE (temporary computer name is p2v-ldjj). Automatic restart to the original operating system is scheduled to occur within 15 minutes. Recommended Action If servername.domainname.com does not restart in 15 minutes, manually restart it back into the original operating system using the boot menu" … during an offline P2V with a computer in a different subnet.
"VMM Cannot find VirtualHardDisk object. Ensure the library object is valid, then try the operation again. ID: 801" … you convert a physical computer to a virtual machine by using VMWare VirtualCenter and one of the disks source computer is larger than 256 gigabytes.
You can resolve these issues by downloading and installing this update.