If you’re using the Virtual Server Migration Toolkit version 1.1 (VSMT) with Windows Server 2003, you can run into problems with the patch cache. The problem is associated with the fact that VSMT 1.1 requires the .Net 1.1 Framework assembly Microsoft.VirtualServer.Interop version 1.465. Virtual Server 2005 R2 Service Pack 1 (SP1) comes with version 1.603 of the assembly, but that isn’t the prime issue. When Virtual Server 2005 R2 SP1 was being built, the Microsoft development team transitioned to .Net Framework 2.0, so all the assemblies are .Net Framework 2.0 versions. VSMT 1.1 can’t communicate with the newer version of the Microsoft.VirtualServer.Interop assembly because there isn’t an updated version of VSMT compiled with .Net Framework 2.0.

To work around this issue, you need to maintain the MobileP2V server at the Virtual Server 2005 R2 version so that the correct assembly is installed. This won’t affect the Virtual Hard Disks (VHDs) created, but you’ll want to install the virtual machine additions from the SP1 release (build 813) on all migrated virtual machines.