# gpg4usb - Documentation

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# Howto sign a message

NOTE: You can only sign messages, if you have one private key, the file is encrypted for. You can identify the private keys by the "bunch of keys"-image in front of the name in the keylist (in this case Bobby):

There are three four for encrypting a text. We assume, that Bobby wants to sign a message. After this everyone who has his public key can verify the message and ensure, that the message wasn't modified.

#### STEP 1/2: Write the message and check key

First Bobby writes the message to the textedit-field. Then he checks his private key in the keylist.

#### STEP 3: Click sign button

Then Bobby clicks the sign button.

#### STEP 4: Enter passphrase

Now Bobby enters the passphrase of his private key.
NOTE: You can only sign messages, if you have a private key. The private keys are those, with the key-icon in front of the Name in the keylist.

Afterwards the signed message is shown.

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