Applies to:

Windows Server 2008 R2 Service Pack 1 with a Hyper-V role

Note:  You should check http://support.microsoft.com for the latest version of the different files.

 

List of Hyper-V role related hotfixes post SP1 for Windows Server 2008 R2 SP1 as of Jan. 2013:

Originally posted May of 2011, updated Sep. 2012 and Jan. 2013.

2734056 Alt Gr key does not work on a Red Hat Linux virtual machine after you install the Hyper-V role on a computer that is running Windows Server 2008
http://support.microsoft.com/?id=2734056

Update(s):
Vmwp.exe  6.1.7601.22055 

Supersede(s):
2711774 AltGr key does not work in a Red Hat Linux virtual machine on a Windows Server 2008 R2-based computer
2711771 Incorrect available space is displayed in a Linux Hyper-V virtual machine on a Windows Server 2008 R2-based computer
2698672 Pointer in a Linux guest operating system does not work correctly when you rotate the wheel button on the mouse in Windows Server 2008 R2
2608694 You cannot operate one or more virtual machines in Windows Server 2008 R2

2710870 DHCPv4 IP address cannot be obtained after you restart a Hyper-V virtual machine that is running Windows 7 or Windows Server 2008 R2
http://support.microsoft.com/?id=2710870

Update(s):
Dhcpcore.dll  6.1.7601.21989
Dhcpcore6.dll  6.1.7601.21989 

2708549 Stop error when you create a VSS snapshot backup in Windows 7 SP1 or in Windows Server 2008 R2 SP1: "fvevol!FveFilterDeviceControl+1d0"
http://support.microsoft.com/?id=2708549

Update(s):
Volsnap.sys  6.1.7601.21854 
Supersede(s):
2632149 "fvevol!FveFilterDeviceControl+1d0" Stop error when you create a VSS snapshot backup in Windows Server 2008 R2 SP1

2705759 Live migration fails when you perform a live migration of a Hyper-V virtual machine in Windows Server 2008 R2
http://support.microsoft.com/?id=2705759

Update(s):
Vmclusres.dll  6.1.7601.22034 

2668084 Virtual machine is restored in the Saved state incorrectly on a Hyper-V server that is running Windows Server 2008 R2
http://support.microsoft.com/?id=2668084

Update(s):
Vmms.exe

Supersede(s):
2668084 Virtual machine is restored in the Saved state incorrectly on a Hyper-V server that is running Windows Server 2008 R2
2666703 You cannot restore a virtual machine that has a semicolon in its name or in its directory path on a Windows Server 2008 R2 SP1-based server
2661530 The whole backup operation fails if one out of several virtual machines on a Hyper-V server cannot be backed up in Windows Server 2008 R2
2547551 Hyper-V Export function consumes all available memory in Windows Server 2008 or in Windows Server 2008 R2
2521348 A virtual machine online backup fails in Windows Server 2008 R2 when the SAN policy is set to "Offline All"
2496089 The Hyper-V Virtual Machine Management service stops responding intermittently when the service is stopped in Windows Server 2008 R2

2665347 You cannot connect to a virtual machine by using the Hyper-V Manager MMC snap-in in Windows Server 2008 R2
http://support.microsoft.com/?id=2665347

Update(s):
Rdp4vs.dll  6.1.7601.21939
Rdp4vs.mof 

2662288 A differencing VHD file that is created by using Microsoft iSCSI Software Target 3.3 becomes corrupted when you mount or attach it in Windows Server 2008 R2 or in Windows 7
http://support.microsoft.com/?id=2662288

Update(s):
Vhdmp.sys  6.1.7601.21891 
Supersede(s):
2614122 Windows Server 2008 R2-based computer may stop responding when dynamic VHDs that are created on the computer experience high I/O activity

2636573 FIX: The guest operating system may crash when you perform a live migration of Hyper-V virtual machines in a Windows Server 2008 R2 environment
http://support.microsoft.com/?id=2636573

Update(s):
Passthruparser.sys  6.1.7601.17514
Storvsp.sys  6.1.7601.21854
Vhdparser.sys  6.1.7601.17514 

2587660 Memory dump file is generated very slowly on a Hyper-V virtual machine that uses Dynamic Memory when the Maximum RAM setting is over 4 GB in Windows Server 2008 R2
http://support.microsoft.com/?id=2587660

Update(s):
Vmwp.exe  6.1.7601.21897 
Vid.dll  6.1.7601.21897 
Vid.sys  6.1.7601.21897

2752183 You cannot migrate a Hyper-V virtual machine from a non-Bulldozer-based computer to a Bulldozer-based computer in Windows Server 2008 R2
http://support.microsoft.com/?id=2752183

Update(s):
Hvax64.exe
Hvboot.sys
Hvix64.exe

Supersede(s):
2740390 Hypervisor does not provide timer services correctly on a Windows 2008 R2-based Hyper-V server
2586470 A saved virtual machine crashes on resume when it hits a debugging breakpoint in Windows Server 2008 R2
2568088 Virtual machine does not start on a computer that has an AMD CPU that supports the AVX feature and that is running Windows Server 2008 R2
2550569 "0x20001" Stop error when you start a Linux VM in Windows Server 2008 R2 SP1
2526776 An update that enables Windows 8 or Windows Server 2012 to be hosted in a Hyper-V virtual machine on 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
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
2263829 The network connection of a running Hyper-V virtual machine may be lost under heavy outgoing network traffic on a computer that is running Windows Server 2008 R2 SP1

2546706 A Windows Server 2008 R2-based computer that has some NUMA-based processors and more than 256 logical processors runs in SMP mode as a 64-processor system and may experience decreased performance
http://support.microsoft.com/?id=2546706

Update(s):
Hal.dll  6.1.7601.21725 

2534356 Some CPU cores are parked while other active CPU cores have a heavy workload in Windows Server 2008 R2
http://support.microsoft.com/?id=2534356

Update(s):
Ntkrnlpa.exe  6.1.7601.21702
Ntoskrnl.exe  6.1.7601.21702 

2519946 Timeout Detection and Recovery (TDR) randomly occurs in a virtual machine that uses the RemoteFX feature in Windows Server 2008 R2
http://support.microsoft.com/?id=2519946

Update(s):
Synth3dvsc.sys 6.1.7601.21677
Synth3dvsp.sys 6.1.7601.21677

2485986 An update is available for Hyper-V Best Practices Analyzer for Windows Server 2008 R2
http://support.microsoft.com/?id=2485986

Update(s):
Hyper-v_model.ps1

Reference:

----------

Comprehensive List of Hyper-V Updates

http://technet.microsoft.com/en-us/library/dd430893(WS.10).aspx

Hyper-V Update List for Windows Server 2008 R2

http://technet.microsoft.com/en-us/library/ff394763(WS.10).aspx

Articles related to Hyper-V, but not hotfixes:
========
2698995 Microsoft support policy for Hyper-V environments utilizing Network Attached Storage
http://support.microsoft.com/?id=2698995

2681638 - Network connectivity is lost on Hyper-V VMs if VMQ feature is enabled on HOST network cards
http://support.microsoft.com/?id=2681638

2526776 An update that enables Windows 8 or Windows Server 2012 to be hosted in a Hyper-V virtual machine on Windows Server 2008 R2
http://support.microsoft.com/?id=2526776