Windows ran an endless “trying to repair” loop but would not budge at all. I made the decision to connect the drive that Windows was installed on to another computer system, to run checks on it. One of those checks was the system file check using sfc.exe. Run SFC /Scannow on external drives. This is sorta a two part question. I have an external drive that when I hook it up the Win 10 Action Center Pane tells me there may be errors.

• Sfc Scannow Specific Drive
• Run Sfc On External Drive Driver
• Sfc Scan External Drive

Original title: SFC and DISM to repair a different (non-boot) driveMy problem is this:I have a computer I built, for windows 7, then upgraded to windows 10. It worked fine except for it would crash upon going into power saving mode. I tried to identify the problem using verifier, but that just crashed my computer, though I did determine theproblem was AMDXATA.sys. After some troubleshooting and a system restore, it would crash while loading windows (BSOD) with the error INACCESSABLEBOOTDEVICE.

After more troubleshooting (with windows PE), I ended up installing windows 10 enterprise on myother hard drive (1TB HDD formatted GPT) so I could get back to my life.My set up is like this:AMD A10-7850KASRock FM2A88X Extreme4+ FM2+ (UEFI capable)2.5' 480GB SATA SSD (where the original installation exists, volume D: NTFS)2TB SATA HDD (where the new installation exists, obviously not the boot drive volume C: GPT)What I want to do:Repair the old installation because I no longer have the activation code and don't want to have to reroll it. I have determined so far in my troubleshooting that switching between UEFI/non-UEFI and NTFS/GPT is a nightmare, especially while executing commandsin command prompt.

While in the PE, I had done chdsk which eventually worked and reported no bad sectors. I also tried sfc and got 'verification 100%, resource protection could not perform requested operation' and tried a lot of things to solve that with noluck.

Sfc Scannow Specific Drive

I tried some bootrec commands only to get 'boot config data for your PC contains errors'. I tried DISM without any luck since I can't get online with that drive.

Run Sfc On External Drive Driver

I have tried every conceivable method to get into safe mode without any luck. I am awarethat I need to activate the partition using diskpart before troubleshooting, and have administrator access.Since then, I have used EaseUS Partition Master to rebuild the MBR while logged into my new windows installation (C:) which seems to have worked. I still get INACCESSABLEBOOTDEVICE when I try to log in to the old one though. What I want to do is try tofix the broken installation using elevated command prompt on my working drive, but there may be some compatibility issues because it is GPT and the other is NTFS, I'm not sure. Whenever I try to execute any operation, it always executes on C: even though Ihave activated the D: partition in diskpart and executed from the D: root. I even triedD:sfc /scannow /offbootdir=d: /offwindir=d:windowsbut it gives me'Windows Resource Protection found corrupt files but was unable to fix someof them.

Details are included in the CBS.Log windirLogsCBSCBS.log. Forexample C:WindowsLogsCBSCBS.log. Note that logging is currently notsupported in offline servicing scenarios.' Is there any way to use DISM from the command prompt in C: to repair the installation in D:?Thanks for any insight yall have! Hello Andrew,Thank you for posting your issue in Microsoft Community and giving us an opportunity to assist you with this issue.In this case it would be best to perform Reset in your system. You can perform reset from the recovery environment and check if it helps:Step 1:I would suggest you to download an ISO image of Windows 10 and try to create installation media using the Media Creation tool.Installation Media tool:Once the bootable media is created, follow next step:Step 2: Perform Start up Repair.Follow the steps mentioned below to perform Start up Repair:a. Insert the installation DVD orUSB and boot Windows 10 from it.b. Select “ Troubleshooting” from the first Window and then select “ Reset your PC”.c. Then select Keep my files and follow the onscreen instruction.This will help you to boot into your Operating system again.Let us know the results.

We will be glad to assist you further.Thank you. Hello again,I have yet to resolve this, I was hoping you could give me some help with the commands I mentioned, or perhaps an alternative.I have poured over these and other forums, so believe me when I tell you that I have tried all of these basic troubleshooting tasks and many others. I have identified several problems with the boot installation and possibly with the boot record that I believecan be solved with the right commands. I have been trying to use the DISM command without success due to my inexperience, but I think it will work if I get the syntax right. I also don't know if it would be better to try these commands from the second harddrive (which I'm using right now), or use the PE USB instead.Thank you for your help,Andy. Hello Andrew,We apologize for delay in responding.Try the below steps and check if it works for you:As the Start up repair doesn’t help to repair the startup files, you may try to repair them using these commands through Command Prompt under Advance Options.Refer to the steps:a) After you boot the computer usingWindows 10 DVD or System Repair Disc, a black screen appears with gray text ' Press any key to boot from CD or DVD'.

Press any key.b) Select the correct time and Keyboard type.c) Click Repair your computer in the lower left corner.d) Select Troubleshoot from Choose an optionscreen.e) Click advanced options in Troubleshoot screen.f) Click on command Prompt.g ) Type these following commands and hit enter after each line of command:Bootrec /fixmbrBootrec /fixbootBootrec /scanosBootrec /rebuildbcdReply to the post with updated status of the issue so that we can assist you further.Thank you. Thank you for the reply.As stated in my original post, I can use these commands with success (though at times varied outcomes). In this case, all were a success, with the /scanos command revealing 2 operating systems: (1) D:windows, (2) C:windows. If it helps, the physical locationof C:windows (the damaged drive) is disk 0, partition 1.I also managed to damage my D:windows installation somewhat after using the /rebuild command on it. After I switched back to that drive (boot), I got a BSOD for winload.exe, which like I said before, I think it has something to do with the file system discrepancybetween the USB recovery console and the GTP HDD. I fixed that though.Still getting INACCESSABLEBOOTDEVICE.

Sfc Scan External Drive

HI,Thank you for getting back with a reply.I do appreciate your efforts and time. Do not worry, will assist you with the issue.The INACCESSIBLEBOOTDEVICE bug check has a value of 0x0000007B. This bug check indicates that the Microsoft Windows operating system has lost access to the system partition during startup.CauseThe INACCESSIBLEBOOTDEVICE bug check frequently occurs because of a boot device failure. During I/O system initialization, the boot device driver might have failed to initialize the boot device (typically a hard disk).

File system initializationmight have failed because it did not recognize the data on the boot device. Also, repartitioning the system partition or installing a new SCSI adapter or disk controller might induce this error.I suggest you to try the steps provided by, in the link below.Hope this helps in resolving the issue. If the issue persists, do get back to us. We will be happy to assist you.