Retrieving encrypted files/photo and videos
As the title states "I need help"
The files were encrypted with EFS on an old desk top with 8.1 in 2015-16
the machine had gotten a bad virus and died with the blue screen of death. In my attempts to save what files I could, microsofts only advice and the only help I was getting, was to upgrade the computer to widows 10 with an ISO file on a flash drive acquired from microsoft online with another computer. While downloading it to the computer windows 10 gave me an opportunity to save all my files to a external hard drive or the computer. I chose external because I wasn't sure the upgrade would fix the computer. It also asked "Do you want to encrypt these files" and I did. But something went wrong and an error message said something about not being able to save the files. When the win 10 upgrade finished and I looked for my files and they weren't on the computer but I did find over 90% of them on the flash drive I left in the back of the computer. The files wanted an encryption key that was now gone. I did learn about Properties and taking ownership along with giving permissions after that. Most of the files I finally deleted and some I was able to open but after seven years I am still baffled by this one file with photos and videos on it. All irreplaceable videos of my son over the years 2003=2016. I have tried everything imaginable over the years to open this file and it can not be moved off the external hard drive as well. It copies the file but no contents. In properties of this file I do have the original User name and Credential thumbprint. It says only that person can access the files. I tried using that info to open it to no avail. We've been through several computers since and pull out the old external to try again.
So any newer suggestions or help would be greatly appreciated. I would list everything that's been tried and tried again over the years but its easier to wait to attach any info until I can see what route some may suggest.
I apologize for the size of this post.