{"id":3074,"date":"2025-12-01T14:58:53","date_gmt":"2025-12-01T12:58:53","guid":{"rendered":"https:\/\/itsimple.info\/?p=3074"},"modified":"2025-12-01T16:46:20","modified_gmt":"2025-12-01T14:46:20","slug":"windows-server-2012-r2-can-not-boot-on-hyper-v-windows-server-2025-error-inaccessible_boot_device","status":"publish","type":"post","link":"https:\/\/itsimple.info\/?p=3074","title":{"rendered":"Windows Server 2012 R2 can not boot on Hyper-v Windows server 2025 error INACCESSIBLE_BOOT_DEVICE"},"content":{"rendered":"\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\" id=\"fixwindowsserver2012r2vmbooterror0x7bonhyperv2025\">\ud83d\udee0 Fix Windows Server 2012 R2 VM Boot Error 0x7B on Hyper-V 2025<\/h1>\n\n\n\n<p>If you&#8217;ve recently migrated a physical Windows Server 2012 R2 machine to a Hyper-V 2025 environment and encountered a blue screen with the error code <code>0x0000007B (INACCESSIBLE_BOOT_DEVICE)<\/code>, you&#8217;re not alone. This guide walks you through a proven registry fix to resolve the issue.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"whatcausesthe0x7berror\">\u26a0\ufe0f What Causes the 0x7B Error?<\/h2>\n\n\n\n<p>This error typically occurs when Windows cannot access the boot device. In the context of Hyper-V 2025, recent cumulative updates (e.g., KB5060842) have changed how virtual hardware is presented to guest VMs. As a result, Windows Server 2012 R2 may fail to recognize the boot device due to outdated or mismatched drivers.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"stepbystepregistryfixofflinemethod\">\u2705 Step-by-Step Registry Fix (Offline Method)<\/h2>\n\n\n\n<p>Follow these steps to repair the registry and restore boot functionality:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step1bootintowindowsrecoveryenvironmentwinre\">Step 1: Boot into Windows Recovery Environment (WinRE)<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Attach a Windows Server 2012 R2 ISO to the VM.<\/li>\n\n\n\n<li>Boot the VM from the ISO.<\/li>\n\n\n\n<li>On the setup screen, click <strong>Repair your computer<\/strong>.<\/li>\n\n\n\n<li>Navigate to:\\ <code>Troubleshoot<\/code> \u2192 <code>Advanced Options<\/code> \u2192 <code>Command Prompt<\/code>.<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step2loadtheofflineregistryhive\">Step 2: Load the Offline Registry Hive<\/h3>\n\n\n\n<p>In the Command Prompt, type:<\/p>\n\n\n\n<p>reg load HKLM\\TempHive C:\\Windows\\System32\\config\\SYSTEM<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step3copymissingacpidevicekeys\">Step 3: Copy Missing ACPI Device Keys<\/h3>\n\n\n\n<p>Run the following commands to replicate the necessary ACPI entries:<\/p>\n\n\n\n<p>reg copy HKLM\\TempHive\\ControlSet001\\Enum\\ACPI\\VMBus HKLM\\TempHive\\ControlSet001\\Enum\\ACPI\\MSFT1000 \/s<\/p>\n\n\n\n<p>reg copy HKLM\\TempHive\\ControlSet001\\Enum\\ACPI\\Hyper<em>V<\/em>Gen<em>Counter<\/em>V1 HKLM\\TempHive\\ControlSet001\\Enum\\ACPI\\MSFT1002 \/s<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step4optionalensurestoragedriverisenabled\">Step 4: (Optional) Ensure Storage Driver is Enabled<\/h3>\n\n\n\n<p>To ensure the Hyper-V storage driver is set to start at boot:<\/p>\n\n\n\n<p>reg add HKLM\\TempHive\\ControlSet001\\Services\\storvsp \/v Start \/t REG_DWORD \/d 0 \/f<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step5unloadtheregistryhive\">Step 5: Unload the Registry Hive<\/h3>\n\n\n\n<p>reg unload HKLM\\TempHive<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step6rebootthevm\">Step 6: Reboot the VM<\/h3>\n\n\n\n<p>shutdown \/r \/t 0<\/p>\n\n\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-e855f033ab35eded3184a1dddda9acb9\">You can download the zip with the registry settings as a .reg file from <a href=\"https:\/\/itsimple.info\/wp-content\/uploads\/2025\/12\/hyperv_2012r2_boot_fix-1.zip\" data-type=\"link\" data-id=\"https:\/\/itsimple.info\/wp-content\/uploads\/2025\/12\/hyperv_2012r2_boot_fix-1.zip\"><strong>https:\/\/itsimple.info\/wp-content\/uploads\/2025\/12\/hyperv_2012r2_boot_fix-1.zip<\/strong><\/a><\/p>\n\n\n\n<p>including the missing driver file storvsp.sys  should be in : c:\\Windows\\system32\\drivers<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"afterrebootwhattocheck\">\ud83e\uddea After Reboot: What to Check<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The VM should boot normally.<\/li>\n\n\n\n<li>In Device Manager, confirm that:\n<ul class=\"wp-block-list\">\n<li>\u201cMicrosoft Virtual Machine Bus\u201d appears under System Devices.<\/li>\n\n\n\n<li>No yellow exclamation marks are present.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Registry path <code>HKLM\\SYSTEM\\CurrentControlSet\\Enum\\ACPI<\/code> should now include <code>MSFT1000<\/code> and <code>MSFT1002<\/code>.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"notes\">\ud83d\udcdd Notes<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>This fix addresses a compatibility issue introduced by Hyper-V 2025 updates.<\/li>\n\n\n\n<li>If the issue persists, consider uninstalling KB5060842 from the Hyper-V host or hosting the VM on an older Hyper-V version temporarily.<\/li>\n\n\n\n<li>There is already another post I have made regarding windows boot error after P2V : <a href=\"https:\/\/itsimple.info\/?p=614\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>https:\/\/itsimple.info\/?p=614<\/strong><\/a><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\ud83d\udee0 Fix Windows Server 2012 R2 VM Boot Error 0x7B on Hyper-V 2025 If you&#8217;ve recently migrated a physical Windows Server 2012 R2 machine to a Hyper-V 2025 environment and encountered a blue screen with the error code 0x0000007B (INACCESSIBLE_BOOT_DEVICE), you&#8217;re not alone. This guide walks you through a proven registry fix to resolve the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20,21,4,12,18,19,14],"tags":[],"class_list":["post-3074","post","type-post","status-publish","format-standard","hentry","category-hyper-v","category-operating-systems","category-tech","category-tutorials","category-virtualization","category-vmware","category-windows"],"_links":{"self":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts\/3074","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3074"}],"version-history":[{"count":4,"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts\/3074\/revisions"}],"predecessor-version":[{"id":3081,"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts\/3074\/revisions\/3081"}],"wp:attachment":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3074"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3074"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3074"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}