How to Encrypt and Decrypt a File. Encrypting files on your computer helps to secure your data from unauthorized access. Microsoft Windows features the native ability to encrypt files and folders ...

To decrypt files using gpg4win, right-click the encrypted file and select Decrypt and Verify. The first two options (related to the signature and archive) should automatically default to the ...

Encryption basically scrambles your data, or in this case your postcard, to make it unreadable to anyone else unless they know the special key or password to open it up.