This page deals with tools and methods that add encryption, digital signatures, or rights management to individual messages. For tools dealing with securing Microsoft Outlook and Microsoft Exchange data with folder and user permissions, see:
To add encryption and security signatures to Exchange messages on the Internet, you can use either PGP (Pretty Good Privacy) or S/MIME (Secure MIME.) S/MIME support is built into Outlook, starting with Outlook 98. See:
- OL2000 - Encryption and Message Security Overview
- OL2002 Encryption and Message Security Overview
Choose Tools | Options | Security. You can add S/MIME support to earlier versions with third-party utilities. CW users note: OL2000 (CW): Rich Text Signed Messages Are Always Sent As HTML. With Outlook 97, you can tell that you've received an S/MIME message if it has an attachment with one of these extensions:
| .p7s | Signed, but not encrypted |
| .p7c | Certificate only, no digital signature or encryption |
| .p7m | Signed and encrypted. Cannot be read except by an S/MIME client |
Outlook 2000 SR-1/1a adds support for S/MIME version 3, but most features need to be activated via Windows registry settings.
Public key servers and other services are listed at Secure E-mail Services
Tools and utilities which do not fit any of the above categories are list at Encryption and Message Security Tools
S/MIME Encryption
Tools
Email Classifier labels enforce the organisation's rules on handling and release of email, automatically invoking other technologies such as encryption or rights management. | |
Encryptomatic OpenPGP for Outlook installs easily, and integrates with the Outlook toolbar. Send encrypted and signed emails using the OpenPGP standard. Compatible with GPG and Enigmail. Support for key servers and key revocation. A single signed installer package with MSI available for wider deployment. Key strengths supported up to 4096 bits. For Outlook 2016 through 2007, 64 and 32 bit versions. Free for personal use. | |
With MessageLock, you can encrypt your email message and/or file attachments using encryption as strong as AES-256 bit (U.S. Government standard). Or you can send a self-decrypting .exe file that will prompt the recipient for a password before decrypting the message. MessageLock can also collect and manage your passwords, both for sending and receiving encrypted files. This allows MessageLock to encrypt with a single click, and decrypt inbound messages automatically. Also adds integrated Zip Compression. For Outlook 2000 through 2007. | |
Component of military messaging client based on Outlook supports S/MIME v.3 encryption and signatures. |
PGP Encryption
Tools
Encryptomatic OpenPGP for Outlook installs easily, and integrates with the Outlook toolbar. Send encrypted and signed emails using the OpenPGP standard. Compatible with GPG and Enigmail. Support for key servers and key revocation. A single signed installer package with MSI available for wider deployment. Key strengths supported up to 4096 bits. For Outlook 2016 through 2007, 64 and 32 bit versions. Free for personal use. | |
"Pretty Good Privacy" encryption, available in both free and commercial versions. See: OAER Outlook Stops Responding and You Receive an Error That References the Pgpexch.dll File |
More Information
- Compression Tools -- Some of these tools can encrypt as well as compress attachments.
- Crypto Law Survey -- Encryption of e-mail is not universally legal. This site tracks encryption law around the world.
- X.400 Services
- OL2002- Exchange 2000 Account with Revoked Security Can Send and Receive E-mail
- Outlook S/MIME Vulnerability
- OL2002 Recipients Cannot Read Messages When 168-Bit (3DES) Encryption Is Enabled -- discusses UseAlternateDefaultEncryptionAlg registry value
- You Cannot Send Encrypted E-Mail Messages to a Contact While You Are Working Offline -- hotfix available for Outlook 2002
- Windows Prompts You for Your Password Multiple Times When You Use Outlook If Strong Private Key Protection Is Set to High -- hotfix available for Outlook 2002
- Quick Start for SMIME in Exchange Server 2003
- OL2002 Recipients Cannot Read Messages When 168-Bit (3DES) Encryption Is Enabled
- Signed E-Mail Message Displays the Incorrect Sending Address
Here is the simple tool that can be used in Outlook for sending and recieving encrypted and secured e-mails. The tool name is PDF Postman for Outlook. Try it now.