The latter allowed rapid copying of single files, two files selected together, and 5 files selected together ( much slower ), but 10 files produced a very slow copy time and 20 files or more crashed the File Explorer.

The Microsoft analyst on the forum suggested system maintenance trouble shooting, turning off autotuning, and remote differential compression. Since upgrading to Windows 10 trying to copy a block of 20 files or more from my camera to the hard drive causes File explorer to freeze and crash. There was no problem doing this in Windows 7. I copy photo files from my Canon DSLR to my external hard drive in File Explorer in Windows. Maybe you would have a different perspective on this problem.

The actual Administrator account allowed me to run the tests on my copying problem suggested by the Microsoft Forum responder who is helping me with this problem. This has to be done with the command prompt in an elevated command window. I had to research how to turn on the hidden administrator account in Windows 10. I already have administrative rights on this computer.

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