Hi We have a Windows Server 2008 x64 machine in the datacentre that is freezing unexpectedly. We use the server to host Virtual Machines, so there's literally nothing installed except for the Hyper-V and FileSharing Roles, and 3 Virtual Machines. Known symptoms are: OS and desktop screen freezes completely; keyboard and mouse not responding at allServer and the Virtual Machines are not pinging - Remote Access not working Websites and the webserver hosted on the Virtual Machines are down (not accessible).Nothing documented in logs, except for 2 unexpected shutdown errors after phisically restarting. Server froze once while creating a new VM, and on multiple occasions while copying large files to the server from external HDD.Server also froze while nobody was operating, or no backups were running, i.e. at 9pm on a Sunday. I've recently replaced the HDDs, thinking this might be the cause, but the server froze even while copying the VMs back immediately after the reinstall. Is there a hotfix for this issue? Many thanks UICL

Hi, Do you see any errors in event logs ? You might want to update the firmwares for the server in question, especially firmwares for NICs. If there are any USB devices attached on the server, please remove them for time being and perform a cleanboot action on the server to isolate the problem. A UNIVERSE without WINDOWS is CHAOS ! This posting is provided "AS IS" with no warranties or guarantees and confers no rights. About Me !!!

Hello, Please proceed like that on this server: Install its latest updatesPerform a clean boot: http://support.microsoft.com/kb/929135Install latest versions of driversDisable temporary security softwares on this serverRun memtest86+ to check that is okay with your RAM (You can do it during a weekend). If an error was detected then replace the faulty RAM or contact your manufacturer Technical Support for assistance If this does not help, I would recommend asking them here: http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/threads This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner 2010 / 2011 Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Applications Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows 7, Configuring Microsoft Certified Technology Specialist: Designing and Providing Volume Licensing Solutions to Large Organizations Microsoft Certified IT Professional: Enterprise Administrator Microsoft Certified IT Professional: Server Administrator Microsoft Certified Trainer

Also, refer a similar discussion Server 2008 SP2 becomes unresponsive, running Hyper-V, VM reside on an ISCSI drive http://social.technet.microsoft.com/Forums/en-US/winservergen/thread/8e53126f-91fa-426c-8536-ccb659ac3895A UNIVERSE without WINDOWS is CHAOS ! This posting is provided "AS IS" with no warranties or guarantees and confers no rights. About Me !!!

Hi. I've already mentioned there's nothing documented in the event logs. And I don't have any usb devices connected. Thanks

In a situation like this I alway recommend running perfmon to capture the server activity up to the point of failure. You need to capture the minimal counters including Hyper-V, Memory, Process, Processor, Logical Disk and Network. Happy to take a look at the results if you want to share out the perfmon capture. or run it through the PAL tool: http://pal.codeplex.com/ Take a look at this article for futher advice: http://social.technet.microsoft.com/wiki/contents/articles/the-microsoft-pfe-performance-guide-perfguide-start-here.aspx

Hi, In addition, do you encountered any BSOD? If BSOD is encountered, you may update BIOS and other hardware drivers first. If it does not work, you may analyze them with Debugging Tools by yourself. You can install it and its Symbol Packages from the following link: http://www.microsoft.com/whdc/Devtools/Debugging/default.mspx WinDbg will tell you the possible cause. For more information, please read Microsoft KB Article: How to read the small memory dump files that Windows creates for debugging http://support.microsoft.com/kb/315263 Collect Minidump Files ================= 1. Click "Start", input "SYSDM.CPL" (without quotation marks) in the Search bar and press Enter. 2. Switch to the "Advanced" tab and click the "Settings" button under "Startup and Recovery". 3. Under "Write debugging information" section, make sure the "Small memory dump (128KB)" option is selected. 4. Make sure "%SystemRoot%\Minidump" is in the "Small dump directory" open box and click OK. If the Blue Screen appears again, please refer to the following steps to collect memory dump files: 1. Click Start, type %SystemRoot%\Minidump" (without quotation marks) in Search bar and press Enter. 2. Go to your Desktop, right-click on it and create a new folder named "Dump". 3. Copy all the memory dump files (looks like [Mini092008-01.dmp]) in Minidump to this folder. If no clue can be found, you may contact Microsoft Customer Service and Support (CSS) via telephone so that a dedicated Support Professional can assist with your request. To troubleshoot this kind of kernel crash issue, we need to debug the crashed system dump. Unfortunately, debugging is beyond what we can do in the forum. Please be advised that contacting phone support will be a charged call. To obtain the phone numbers for specific technology request please take a look at the web site listed below: http://support.microsoft.com/default.aspx?scid=fh;EN-US;OfferProPhone#faq607 Regards,Arthur Li TechNet Community Support