Applies to:

Windows Server 2008 R2 RTM with a Hyper-V role

Note:  You should check for the latest version of the different files.

List of Hyper-V role related hotfixes post RTM for Windows Server 2008 R2 RTM as of April 2011:


2485986 An update is available for Hyper-V Best Practices Analyzer for Windows Server 2008 R2



2517374 You cannot start virtual machines on a computer that is running Windows Server 2008 R2 and on which a CPU is installed that supports the AVX feature

Hvax64.exe 6.1.7600.20916

Hvboot.sys 6.1.7600.20916

Hvix64.exe 6.1.7600.20916

Note: W2K8 R2 RTM

Note: This hotfix supersedes:

2517329 Performance decreases in Windows Server 2008 R2 when the Hyper-V role is installed on a computer that uses Intel Westmere or Sandy Bridge processors

2264080 An update rollup package for the Hyper-V role in Windows Server 2008 R2: August 24, 2010

2133637 The computer stops responding at startup in Windows Server 2008 R2 if you enable the Hyper-V role and if you have more than 512 GB of RAM

981791 “STOP: 0x0000001a” error message on a computer that has an Intel Westmere processor together with the Hyper-V role installed on Windows Server 2008 or on Windows Server 2008

981618 Computer hangs or restarts during Hyper-V Live Migration

974909 The network connection of a running Hyper-V virtual machine is lost under heavy outgoing network traffic on a Windows Server 2008 R2-based computer


981836 Network connection is lost on a Windows Server 2003-based Hyper-V VM


Netvsc50.sys 6.1.7600.20683

Netvsc60.sys 6.1.7600.20683

Netvscres.dll 6.1.7600.16385

Passthruparser.sys 6.1.7600.16385

Storvsp.sys 6.1.7600.20683

Vhdparser.sys 6.1.7600.16385

Vmbus.sys 6.1.7600.20683

Vmbuscoinstaller.dll 6.1.7600.16385

Vmbuspipe.dll 6.1.7600.16385

Vmbusres.dll 6.1.7600.16385

Winhv.sys 6.1.7600.16385

Vmsntfy.dll 6.1.7600.20683

Vmswitch.sys 6.1.7600.20683


2223005 The network connection is lost on a Hyper-V virtual machine

Netvsc50.sys 6.1.7600.20743

Netvsc60.sys 6.1.7600.20743

Netvscres.dll 6.1.7600.16385

Note: This partially supersedes 981836

2521348 A virtual machine online backup fails in Windows Server 2008 R2 when the SAN policy is set to "Offline All"

Vmms.exe 6.1.7600.20927

Note: This hotfix supersedes:

2496089 The Hyper-V Virtual Machine Management service stops responding intermittently when the service is stopped in Windows Server 2008 R2

2518021 Hyper-V virtual network adapter does not bind to Quality of Service (QoS) in Windows Server 2008

Wvms_mp.inf 17-Mar-2011


Informational KB’s:


975426 Virtual machines cannot migrate from a Windows Server 2008 stand-alone server to a Windows Server 2008 cluster after you upgrade to System Center Virtual Machine Manager 2008 R2

976097 Hotfix to add support for asymmetric storages to the Failover Cluster Management MMC snap-in for a failover cluster that is running Windows Server 2008 or Windows Server 2008 R2

Note: Fix for W2K8 R2 is to install SP1 for W2K8 R2.

2515143 Using Hyper-V with large sector drives on Windows Server 2008 and Windows Server 2008 R2

2517913 Distributed File System Replication (DFSR) no longer replicates files after restoring a virtualized server’s snapshot

2518791 [SDP 3][a0f578a1-731c-4437-92cf-c246fa98be36] Hyper-V – Windows Server 2008 R2


Comprehensive List of Hyper-V Updates

Hyper-V Update List for Windows Server 2008 R2