Easy Email Encryption
Easy Email Encryption is for sending and receiving encrypted email (optionally with attached files up to 100 KB), and is designed to be easy to use. It works with any email program, including Outlook Express. It uses a symmetric key method, and keys are maintained in an encrypted list of keys... Easy Email Encryption is bilingual, English/German, and works with text in languages other than English. ... In order to prevent others from discovering the keys you use to encrypt messages, the key list must itself be encrypted.
http://www.hermetic.ch/eee/eee_setup.zip - 2Mb - Download - Screenshot

abylon CRYPTMAIL
Sending never again unencrypted emails. With abylon CRYPTMAIL offer abylonsoft a simple software for certificate based encrypting (PKCS-standard) of your secret data. With the AddIn for Outlook (not Outlook Express) you can pack or unpack so-called SME files (Secure Message Envelope = Signing... The SME-file is transmitted by the MAPI-interface to nearly every email program. ... Only the owner of the correct Private Key can open and read the email. ... Additionally offer abylonsoft an user interface to create encrypted and signed emails.
http://www.abylonsoft.de/download/SAOAID.exe - 6Mb - Download - Screenshot

CommuniCrypt Mail
Standalone eMail client with built-in strongest asymmetric Public-Key-Encryption with RSA encryption algorithm (RSAES-OAEP). Key length for encrypting up to 7120 bit. This eMail client is fully featured for receiving/sending mails via POP3/SMTP. With the integrated SMTP engine you do not need a... Encryption/Decryption is optional to enable/disable so can use this great eMail client day by day - not only for your encrypted mails! ... This is an all-in-one solution to protect your Email privacy with the strongest encryption available!
http://www.communicrypt.com/downloads/ccm_setup.exe - 5Mb - Download - Screenshot

Chilkat WebMail ASP Email Component
Powerful POP3/SMTP email client specifically tailored to be used in ASP websites.
ftp://www.chilkatsoft.com/WebMail.exe - 371Kb - Download - Screenshot

CryptArchiver
It's really easy to hide, encrypt and password protect data with CryptArchiver. All you do is drag-and-drop your important files and folders into an encrypted drive - just like an ordinary drive! CryptArchiver has an intuitive and easy-to-use interface. ... When you unload the encrypted drive, it disappears from Windows! ... Load the Encrypted Drive again with the password, to access your files. ... You can protect all types of files - be it email, databases, spreadsheets, text, graphics, audio or even video.
http://www.winencrypt.com/downloads/calite.exe - 1Mb - Download - Screenshot

Public Key File and Email Encryption freeware
DeltaCrypt OneClick Personal does it all: This Public Key Encryption Software encrypts files, text and emails with 1024-bit RSA protection, digital signatures, and unalterable public keys. It offers the basic encryption functionalities FREE OF CHARGE. ... One of the features of DeltaCrypt OneClick Personal is its ease of use with any email or text messaging software. ... From the icon in the System Tray, you can quickly encrypt or decrypt your email text …and then get back to what you were doing.
http://www.deltacrypt.com/next/_demo_/setup.exe - 1Mb - Download - Screenshot

Safe Express Free
What is the need for encrypting email messages you might ask yourself? But if any of your important messages get intercepted and read by other people, it could bring a lot of damage to you. This is where Safe Express comes into play. This software is a powerful, highly configurable, yet easy to... It is also a public key email encryption client that automatically encrypts all your messages and an anti-spam email client that automatically classifies incoming emails as spam or non-spam. ... It also supports drag and drop attachments, for example you can drag attachments from an email on your...
http://www.netsafesoft.com/DEMO/sef.exe - 928Kb - Download - Screenshot

Safe Express Home
What is the need for encrypting email messages you might ask yourself? But if any of your important messages get intercepted and read by other people, it could bring a lot of damage to you. This is where Safe Express comes into play. This software is a powerful, highly configurable, yet easy to... It is also a public key email encryption client that automatically encrypts all your messages and an anti-spam email client that automatically classifies incoming emails as spam or non-spam. ... It also supports drag and drop attachments, for example you can drag attachments from an email on your...
http://soft.safeworld.info/counter...t.safeworld.info/download/seh.exe - 1Mb - Download - Screenshot

PrivateMail for Hotmail
TrustTone PrivateMail is the easiest private email solution available today. Based on patent pending Universal Digital ID and SmartPKI (TM) technologies, PrivateMail provides enterprise level security without any prior setup, use of passwords, or manual key/certificate exchange. ... You are ready to send encrypted HIPAA compliant e-mail and documents to anyone with an email address. ... PrivateMail Free allows an unlimited number of encrypted messages to up to 20 other users. ... Your emails go through your email gateways; NOT through any TrustTone servers.
https://ca.trusttone.com/trustTonePMHotmail.exe - 5Mb - Download - Screenshot

PrivateMail for Outlook
TrustTone PrivateMail is the easiest private email solution available today. Based on patent pending Universal Digital ID and SmartPKI (TM) technologies, PrivateMail provides enterprise level security without any prior setup, use of passwords, or manual key/certificate exchange. ... You are ready to send encrypted HIPAA compliant e-mail and documents to anyone with an email address. ... PrivateMail Free allows an unlimited number of encrypted messages to up to 20 other users. ... Your emails go through your email gateways; NOT through any TrustTone servers.
https://ca.trusttone.com/trustTonePMOutlook.exe - 5Mb - Download - Screenshot