Win Server 2012 R2 Essential cannot boot Windows after Update


  • Hi all,

    I'm having issue that after I installed Windows Update on my Win Server 2012 R2 Essential, the Windows cannot boot. Error shows "inaccessible_boot_device". Google around and find out that the issue cause by update kb2919355 package. I've tried everything and spent my whole night to troubleshoot the issue but everything failed. If some one have any idea what to do, i really appreciate it. Please help because its the production server and it cause the downtime to my company.


    Thursday, May 18, 2017 2:51 AM

All replies

  • Hi,

    I have the same issue on a Windows Server 2016. There is no partition anymore on the system disk!

    The system ist installed on a 128 GB SATA SSD. I will try to recreate partitiontable with TestDisk, otherwise I have to reinstall Windows Server and reconnect the Hyper-V instances. 

    Greetings from Germany


    Thursday, May 18, 2017 7:41 AM
  • Hi again,

    I recoverd my partitions with TestDisk from a GPartedLiveCD (autscanmode).

    Now, i booted with a Windows 2016 DVD and go to repair options/ command line interface.

    Witch diskpart, I activated the 500MB Partition für Bootmgr. (list volumes -> sel Vol "Number" -> acivate)

    Then i run bootrepair with bootrec:

    bootrec /fixMBR
    bootrec /fixboot
    bootrec /rebuildbcd

    Fortunataly, my Server started and everything is ok.

    Oh no, Hyper V would not start....


    BCDedit /Set {current} hypervisorlaunchtype auto

    on commandline and it is going on

    Greetings from Germany



    • Edited by Jan Knizek Thursday, May 18, 2017 9:39 AM
    Thursday, May 18, 2017 9:04 AM
  • Hi,

    Please try to using installation medium to have a boot reparation.

    Detail steps you may reference - Repairing Windows 2012 R2 Startup:

    Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.

    Best Regards,
    Eve Wang

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    Friday, May 19, 2017 7:45 AM