Index Introduction The BCD Store The System BCD Store Default Paths\Setup (BIOS) Default Paths\Setup (UEFI) BCDEdit - The Basics Check Entries in a BCD Store Devices Devices - locate Backing up the BCD Store Examples - Part 1 Examples - Part 2 Examples - Part 3 Examples - Part 4 BCDEdit Commands BCDEdit Versions Mounting the BCD Store... Acknowledgements Appendices ========= Glossary BCDEdit (version 6.0.6001) BCDEdit (version 6.1.7601) BCDEdit (version 6.3.9600) Device Partition - Data Objects and Elements Alternatives to bcdedit UEFI, BIOS, GPT and MBR

BCDEdit Versions

Several versions of BCDEdit are referenced throughout this guide. It should be noted however that every version of Windows released since Vista includes a different file version of bcdedit.exe along with a corresponding version of the Windows Boot Manager (bootmgr and/or bootmgfw.efi).

bcdedit.exe has evolved with each subsequent release of Windows Operating Systems - some commands have been deprecated and new commands have been added as features are added to the Windows Boot Manager. Consequently the version of bcdedit.exe used to edit or create a BCD Store should ideally correspond to the file version of the Windows Boot Manager in use on the system - this is not always possible on Multiboot systems.

The following output from a BCD store is used to illustrate this. The BCD Store was copied from a sysprepped Windows 8.1 system - it shows the OSLOADER entry only (obtained by using the command syntax bcdedit.exe /enum OSLOADER /v [enter]). Elements not enumerated correctly in BCDEdit are unlikely to be interpreted correctly by the corresponding version of the Windows Boot Manager - potentially resulting in boot errors or failure.

6.0.6001.18000

This version of bcdedit.exe was copied from a Windows Vista (SP1) system -
Windows Boot Loader ------------------- identifier {1b7d8ab0-f5dc-11e4-b34f-9b012cb0060f} device unknown path \Windows\system32\winload.exe description Windows 8.1 locale en-US inherit {6efb52bf-1766-41db-a6b3-0ee5eff72bd7} custom:1500004b 1 recoveryenabled No custom:17000077 352321653 osdevice unknown systemroot \Windows resumeobject {1b7d8aaf-f5dc-11e4-b34f-9b012cb0060f} nx OptIn custom:250000c2 1
Note the device and osdevice elements are listed as unknown - the locate type Device was not introduced until the release of Windows 7. There are also three unknown elements listed using custom:xxxxxxxx values (where xxxxxxxx is a hex value for an element).

• custom:1500004b
• custom:17000077
• custom:250000c2

6.1.7601.17514

This version of bcdedit.exe was copied from a Windows 7 (SP1) system -
Windows Boot Loader ------------------- identifier {1b7d8ab0-f5dc-11e4-b34f-9b012cb0060f} device locate=custom:12000002 path \Windows\system32\winload.exe description Windows 8.1 locale en-US inherit {6efb52bf-1766-41db-a6b3-0ee5eff72bd7} integrityservices Enable recoveryenabled No custom:17000077 352321653 osdevice locate=custom:22000002 systemroot \Windows resumeobject {1b7d8aaf-f5dc-11e4-b34f-9b012cb0060f} nx OptIn custom:250000c2 1
Note the device and osdevice elements are now correctly displayed with locate=custom:xxxxxxxx type data. Additionally one of the elements not recognised by the Windows Vista (SP1) version of bcdedit.exe (custom:1500004b) is now correctly interpreted as the integrityservices element. There are still two unknown elements listed using custom:xxxxxxxx values (where xxxxxxxx is a hex value for an element).

• custom:17000077
• custom:250000c2

6.3.9600.17031

This version of bcdedit.exe was copied from a Windows 8.1 (Update 1) system -
Windows Boot Loader ------------------- identifier {1b7d8ab0-f5dc-11e4-b34f-9b012cb0060f} device locate=custom:12000002 path \Windows\system32\winload.exe description Windows 8.1 locale en-US inherit {6efb52bf-1766-41db-a6b3-0ee5eff72bd7} integrityservices Enable recoveryenabled No allowedinmemorysettings 0x15000075 osdevice locate=custom:22000002 systemroot \Windows resumeobject {1b7d8aaf-f5dc-11e4-b34f-9b012cb0060f} nx OptIn bootmenupolicy Standard
All entries are enumerated correctly -

• custom:17000077 - allowedinmemorysettings
• custom:250000c2 - bootmenupolicy