Download from:

http://marknanyang.com/files/drag_and_drop_using_RSA.exe

Screenshots:
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Launch screen.
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Encryption in progress.

The 256bit private and public key will be generated automatically on the fly.
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Save the two figures somewhere for decryption.
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Decryption in progress after drop the .encrypted file into the dialog.

Then the original file will be restored.

Exceptions:
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Note: This program can run on all kinds of files. RSA is slow.