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Communication Security: Remote Access and Messaging • Chapter 3 141

public keys located locally on a desktop or laptop that is already installed on
Outlook and used to decrypt the e-mail received.

TEST DAY TIP
For the Security+ exam, remember that a key ring is always held locally.
Think of your own personal key ring with the keys to your home or car,
since you normally keep your keys with you.

If Outlook cannot find the proper public key to decrypt a message, users will
be prompted to acquire the public key from a key authority. If Outlook already has
the public key, it will decrypt the message so that it can be read. Users should
realize, however, that once decrypted, an e-mail message will remain decrypted
while stored on a machine.
When the e-mail is encrypted, it will change in appearance to anyone viewing
the message. Similar to the following example, the e-mail becomes hashed (trans-
forming a string of characters into a fixed-length value that represents the original
string), so that no one can understand it until it is decrypted:

-----BEGIN PGP MESSAGE-----
Version: PGPfreeware 7.0.3 for non-commercial use <http://www.pgp.com>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=X7eE
-----END PGP MESSAGE-----

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