Open "Network and Sharing center"
Left click "Advanced Sharing center"
Turn off password protection sharing and save changes.
If this doesn't work then unfortunately I don't think I can provide a means for you. Technically Microsoft wants you to use Sysprep for this purpose and so the Copy To... toolset is purposely hampered.
You can
learn more here.
You can also
try this utility. I make no promises that it will work or even a presumption of its safety. It does need to be run as an Admin to carry out this task.
Assuming that one of these fixes the problem for you, please remember to disable the Admin account again and to enable password protected sharing again.
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