Try the DISM method using a freshly created Windows 10 DVD.
Why did things go wrong online? -- If your Internet connection is having trouble, it's hard for DISM to grab the files from Windows Update. Also doesn't work if Windows Update already has issues.
And, remember that the process can take a long time: it is not unusual for it to not update the progress percentage, even though it is progressing in the background. The percentage can jump quite a bit all at once. Progress percentages are a bit iffy for a number of utilites, so we'll go easy on Microsoft on this one.
Here are the instructions for trying DISM again using a Windows 10 DVD:
Microsoft Media Creation Tool for Windows 10
From a clean, working Windows computer, copy & paste the following URL into the address bar of its browser:
http://go.microsoft.com/fwlink/?LinkId=691209
It is a direct link, and the download will begin immediately: downloading to the default location for downloads as set up on that computer.
Then:
1) Double-click the file to run the media creation tool.
2) You'll notice a blue window opens, saying "Getting things ready" ...
3) After a few moments, another screen appears, which includes the option "Create installation media for another PC" choose that.
4) Select the language, edition and architecture (64-bit or 32-bit) for Windows 10.
5) Follow the steps to create the installation media, then select "Finish" when it’s done.
I recommend using a DVD-R or DVD+R disc. Once created, these are read-only, and can't be corrupted or infected by malware (unlike an image on a USB drive). A DVD-R disc only costs about 15 cents, too. You can keep the DVD around after this repair, too -- for it can be used as a repair DVD for any computer using the same type of Windows 10 (same version, same bit length: 64 bit or 32 bit). You can boot with it to run Startup Repair - a popular use.
Running DISM using the Windows 10 DVD
On your troubled computer:
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) Press the key-combination
Windows +
X (press them at the same time)
5) From the menu, select
Search
6) In the search box, type
cmd
7) Right-click the
Command Prompt icon that appears, and choose
Run as administrator
8) 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.
After it's done, run a new SFC check, and see if it reports everything is fine.
Then visit Windows Updates, and see if anything new is ready - install if so.