Summary

Here’s how to rescue your files to external USB when WIndows won’t start.  You can use the Command Prompt in Repair Mode or use bootable Windows installation media, Recovery Drive, or Repair CD.

Details

Files should always be backed up externally since the hard drive can die at any time and they will be unrecoverable.  In addition back valuable files up to the Cloud in case of fire and to have the latest revisions. 

To protect your documents to outer USB when Windows can’t begin, you can utilize whichever technique works here to get to the Command Prompt from Boot, if vital by booting your bootable Windows establishment media, Repair CD or Recovery Drive.

If necessary presently Create Windows 10 Installation Media or Create Installation media for Windows 8.1.

Supplement the bootable Windows establishment media or Recovery drive.

Catalyst the PC, promptly and energetically tap the BIOS Boot Menu Key to choose the media for sure (as a UEFI gadget whenever offered) from menu like this:

If it bypasses the Boot Menu then use the key from chart in same link to enter UEFI firmware or BIOS setup to turn off Fast Boot, and from within Windows you can also change Settings > System > Power & Sleep > Additional Power Settings > Choose what Power buttons do > Change settings that are unavailable > uncheck Fast Startup. See also Four Methods to Access UEFI BIOS Setup in Windows 8/10 PC/Laptop/Tablet

At first screen press Shift + F10 to open a Command Prompt:

If this fails go to the next screen, choose Repair Your Computer,

then Troubleshoot:

Then Advanced Options:

Then Command Prompt.

In Command Prompt type notepad.exe 

In Notepad, click File, then Open.  This will open a Mini-Explorer that you can use to locate folders or individual files needing rescue, right click to Send to USB drive or DVD.  During copying there will be no progress bar and PC will appear to be frozen.  You only need to wait it out as it will unfreeze as soon as the copying is finished.

For instance from booted Windows 10 blaze installer, I picked my Pictures envelope which is 4.7 gb, Sent it to a similar glimmer stick that was booting the PC. On a Core i5 Lenovo Laptop with 8 gb RAM, it took 10 minutes to duplicate the whole envelope after which I could proceed varying.

Prior to proceeding onward to reinstall Windows, after you’re certain replicating has completed, Close the order Box, expel salvage media, put it in another PC to watch that everything is there – particularly that no organizer was just halfway duplicated.