Generally, the DISM tool is helpful when SFC finds but can't repair corrupt files. The DISM process provides a refreshed image. Whenever a user has trouble with the online process, I often recommend trying again using a Windows 10 DVD as a source. Besides, it can be handy to have a Windows 10 DVD around ... for startup repairs ... and as a source of system files for other repair emergencies.
Here are the instructions to create a Windows 10 DVD, and the steps for DISM to use the Windows 10 DVD as the source.
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Create a bootable Windows 10 DVD
Go to the Microsoft "Get Windows 10" website:
Windows 10
1) Once on the Get Windows 10 site, scroll down to the section "
Need to create a USB, DVD, or ISO?"
2) Click on the blue option button "
Download tool now"
Once the download is complete, double-click
MediaCreationTool.exe
3) "Getting things ready" will appear for a bit.
4) Agree to the License Terms by clicking on
Accept
5) Again, "Getting a few things ready" will appear.
6) On the following screen, select "
Create installation media for another PC".
7) And click
Next.
8) Select your preferences:
language, Windows 10 version, bit-depth (the defaults are English, Windows 10, 64-bit)
9) Select
ISO file.
If the iso is created on a computer already running Windows 10, simply put a blank DVD in the optical drive, right-click the .iso file you created & select "burn disk image". Otherwise use a DVD burning capable program (Roxio, Nero, Sonic, CyberLink, etc.) to create the bootable DVD -- look for a "burn image" option. You must use that special command, because simply copying the file to a DVD doesn't make the DVD bootable, it must be written as a system image (otherwise it ends up as a normal storage DVD that happens to have an .iso file on it).
Running DISM using a Windows 10 DVD
1) Make sure you are
disconnected from the Internet. No Ethernet cable. Turn off the wireless.
2) Place the
Windows 10 DVD in the DVD drive - cancel or exit out of any resulting screens.
3) Note the
drive letter assigned to your
DVD drive (you'll see this in File Explorer)
4)
Right-click the
Windows Start Menu icon
5) From the menu, select
Command Prompt (Admin)
6) To the question "
Do you want to allow this app to make changes to your computer?", select
Yes
7) Type in the following command, replacing the "D" in the Source:wim: with the drive-letter assigned to your DVD-drive (if it's different)
Dism /Online /Cleanup-Image /RestoreHealth /Source:wim:\sources\install.wim:1 /limitaccess
(if your DVD drive happens to be assigned the drive-letter D, you can copy and paste that line into your command prompt)
It can take quite a while - varies a bit from machine to machine.
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See if that helps.
Just for curiosity's sake: are there errors in your Event Viewer logs that are worrisome? Are any programs behaving badly? And did you include a standard run of hardware diagnostics -- just to make sure no hardware issues were causing software snafus?