An ordinary guy trying to make a difference
You might want to check out the two hitfixes detailed in this article:
956589 (http://support.microsoft.com/kb/956589/ ) Description of the Hyper-V update for issues that may occur when you manage the Hyper-V role on the 64-bit editions of Windows Server 2008 by using SCVMM
956774 (http://support.microsoft.com/kb/956774/ ) A Background Intelligent Transfer Service (BITS) client cannot handle files that have paths that contain the volume GUID in Windows Server 2008 or in Windows Vista
http://support.microsoft.com/?kbid=962941
Read the complete post at http://wmug.co.uk/blogs/cliffs_blog/archive/2009/02/12/scvmm-kb-962941-recommended-hotfixes-for-system-center-virtual-machine-manager-2008.aspx