How do I decrypt a message using PGP?

Using PGP with Microsoft Outlook

If you installed PGP with the Microsoft Outlook plug-in, PGP puts controls on the icon bars in the Outlook main window, in the New Message window, and in the window where received messages are displayed. These icons let you decrypt and verify messages, encrypt messages, digitally sign messages, encrypt and digitally sign messages, and start PGPkeys.

Note: Outlook does not make the full message available to PGP. For this reason, PGP encryption will cause text formatting (font and color choice, for example) to be lost. Also, attachments will be sent in the clear. You can work around this in several ways. You can separately encrypt files to be attached, and attach the encrypted versions. You can compose a formatted message using Wordpad or Word, save the message as an RTF file, encrypt the RTF file using PGP, and send the encrypted file as your message.

When you receive a message encoded with PGP, it will look like the message above. Click on the "Decode and verify" PGP tool on the tool bar to decode the message and verify any attached signature. PGP will copy the encrypted message to the Windows clipboard, decode it, and display it in the secure message viewer.

To send a message encrypted with PGP, compose the message normally. Before you send it, click on the Encrypt Message Before Sending and/or the Sign Message Before Sending buttons at the top right corner of the new message window. PGP will encrypt the message to the addressees of the message, and replace the cleartext message body with the encrypted message body.

Using PGP with Microsoft Outlook Express

If you installed PGP with the Microsoft Outlook Express plug-in, PGP puts controls on the icon bars in the New Message window and in the window where received messages are displayed. These icons let you decrypt and verify messages, encrypt messages, digitally sign messages, encrypt and digitally sign messages, and start PGPkeys.

Note: Outlook Express does not make the full message available to PGP. For this reason, PGP encryption will cause text formatting (font and color choice, for example) to be lost. Also, attachments will be sent in the clear. You can work around this in several ways. You can separately encrypt files to be attached, and attach the encrypted versions. You can compose a formatted message using Wordpad or Word, save the message as an RTF file, encrypt the RTF file using PGP, and send the encrypted file as your message.

When you receive a message encoded with PGP, it will look like the message above. Click on the "Decode and verify" PGP tool on the tool bar to decode the message and verify any attached signature. PGP will copy the encrypted message to the Windows clipboard, decode it, and display it in the secure message viewer.

To send a message encrypted with PGP, compose the message normally. Before you send it, click on the Encrypt Message Before Sending and/or the Sign Message Before Sending buttons at the top right corner of the new message window. PGP will encrypt the message to the addressees of the message, and replace the cleartext message body with the encrypted message body.

Using PGP with Other Mailers

PGP can be used easily with other mailers, although not quite as easily as the mailers for which it has plug-ins.

If the mailer supports select all, copy, and paste operations (as almost all do), message encryption, signing, and decryption can be performed through the PGPtray program. To sign and/or encrypt an outgoing mail message, first compose it as usual, then click on the PGPtray icon and then on Current Window|Encrypt, Current Window|Sign, or Current Window|Encrypt and Sign. PGP will process the message as desired, and replace the cleartext message in the composition window with the encrypted message. You can then send the processed message in the usual way.

Similarly, a received message can be decrypted in place by clicking on the PGPtray icon, then on Current Window|Decrypt and Verify.

If the mailer does not support window operations, then PGP can still be used by manually moving data to and from the clipboard. After composing the message, select the entire message, and copy the text to the clipboard. The usual menu operation to do this is Edit|Copy. Then, sign and/or encrypt the message with PGPtray by choosing Clipboard|Encrypt, Clipboard|Sign, or Clipboard|Encrypt and Sign. This processes the contents of the clipboard and puts the results back on the clipboard. Finally, replace the cleartext message by pasting the processed message over it. The usual menu operation to do this is Edit|Paste. You can then send the processed message in the usual way.

Similarly, encrypted messages you receive can be decrypted by copying the message to the clipboard, then using the Clipboard|Decrypt and Verify menu option of PGPtray.

Previous / Contents / Next