MessageLock makes it easy to send and receive AES encrypted email messages with Microsoft Outlook.

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Email encryption toolbar Outlook 2007email encryption toolbar Outlook 2003
If you understand these toolbar buttons, you can already use MessageLock. Product Spec Sheet
  • Encrypts Outlook email message and attachments
  • Secures email messages in an AES encrypted zip-compatible envelope
  • Adds zip, unzip and decryption to Microsoft Outlook
  • Widely compatible with Hundreds of Millions of Computers that can already decrypt Zip files
  • Easy to Use, One-Click email Encryption
  • Exceeds HIPAA encryption strength requirements for protecting email.
Email Encryption/Decryption and Zip Compression in a powerful but easy to use utility
MessageLock is an add-in for Microsoft Outlook that allows the sender to protect email messages using strong AES-256 bit encryption (exceeds HIPAA’s minimum strength requirements).
To use MessageLock, just open a new email message in Microsoft Outlook, and click the “Encrypt Email” button in the Outlook email toolbar.
Outlook 2007 encryption toolbar
MessageLock is virtually seamless when both sender and receiver have it installed. MessageLock will automatically decrypt inbound packets, and display the email as a regular message in your Outlook inbox. The decrypted message will be time-stamped, as proof that it was received securely.
Sending Encrypted Messages
When sending email to someone who does not have MessageLock, there are three methods you can shoose from to deliver your message securely:
1. Send using zip-compatible encryption. This method requires that the user have a zip utility (such as or to decrypt the MessageLock file and access the contents. The recipient may already have this software, but if not, it is free to download. Using zip encryption works very well most of the time, but occassionally a firewall may block an encrypted zip file.
2. Require the use of MessageLock Decryptor. This method requires that the recipient download MessageLock Decryptor to open the .ml256 packets that MessageLock creates. The Decryptor can be hosted from your website, if you wish. After installing the Decryptor, the user simply clicks on the .ml256 file to open your message; MessageLock Decryptor will then prompt for the password. This method has proven very reliable in delivering the encrypted packetl.
3. Send a self-decrypting file. This method allows you to create a self-decrypting .exe file which when run, will prompt the recipient for the password. The user does not require any special software. The executable file is delivered in an unencrypted zip wrapper, accessible to Windows XP and Vista without a zip utility.
Whichever method is chosen, MessageLock will remember it, and apply the settings to future encrypted emails to that recipient.
Password Storage
MessageLock can collect and manage your passwords, both for sending and receiving encrypted files. Users can begin using it immediately, and MessageLock will gather the passwords as necessary. Access to the master password list can be protected,
MessageLock email encryption
Use MessageLock to:
  • send secure email messages
  • automatically unzip and decrypt any password protected zip files that you receive
  • secure your file attachments with strong AES-256 zip-compatible encryption
  • easily apply encryption and compression to your entire email message
  • send encrypted emails to multiple recipients or to a group
  • automatically format your email message as either a pdf, mht or msg file, depending on the preference of your recipient
  • combine file attachments into a single smaller zip file
  • gathers your passwords as you send email, then recalls your passwords on future correspondence
System administrators appreciate these features:
  • If it is desirable to do so, you can distribute a “starter” password database. Users can optionally be locked out of password settings.
  • User intuitive: very little training is necessary to use MessageLock.
  • Silent install with command line key registration
  • Install for all user accounts
  • Multiple MessageLock installations can be activated online with a single key
  • For site licenses, or where online activation is not practical, MessageLock can be activated by including a key file in the directory
Who is it for?
MessageLock was designed primarily for people who communicate with midsize to small office professionals or individuals. A recent survey of our users showed us that MessageLock is used by banks, manufacturers, designers, architects, lawyers, social service agencies, educators and CPA’s.
A single click lets you secure financial reports, manuscripts, word documents, contracts, designs, travel plans, power-point slides, login passwords, hotel reservations, photos, source code, set appointments, or any other discreet business or personal information. 
Integrated Zip Compression for Outlook 2010/2007/2003

MessageLock for Outlook will place your documents into an compressed and/or encrypted zip file. It can also create a self-decrypting .exe file. Users who have advanced needs to set rules for compression will find a number of options to configure MessageLock to their specific needs.

MessageLock zip compression

Why Encrypt?
Why is encrypting you documents and email important? Because the information in your email can can be gathered and analyzed as it crosses the internet. Click here for more information on the threat to your email. 
What Kind of Information Should I Protect When Sending an Email?
Governments will often define specific requirements for the kind of information that must be protected.
In our every day lives, we should seek to protect even seemingly routine details or information about ourselves, our families, and our business. Information about where we've been, where we are and where we're going to be.
Here are examples of information that you should seek to keep private in an email.
  • financial reports
  • product performance and sales reports
  • word documents containing drafts or work for hire
  • any information considered embarrassing or confidential
  • any information where there is a reasonable expectation of privacy
  • credit card numbers
  • client lists
  • marketing plans
  • signed contracts
  • contract in progress
  • account statements or balances
  • expense reports
  • business negotiations
  • any discussions involving advice from or requests to a professional advisor, including your your CPA, attorney, banker, or financial advisor
  • discussions about employee performance
  • designs
  • travel plans
  • power-point slide presentations
  • login passwords
  • social security numbers
  • birth dates
  • hotel reservations
  • personal or business photos
  • computer source code
  • set appointments
  • real estate purchase negotiations
  • resumes
  • job applications
  • and much more...
MessageLock makes it easy to add password protection to an email message and/or attached files.
Just type your message, click "Encrypt" and "Send" your email.
Recipient's only need a zip utility, such as WinZip or TugZip, with AES encryption capability. That means that no single use "reader" software is required to access the contents of your encrypted message.
Using the Zip format to deliver strongly secured messages makes it practical to send and receive encrypted files. Most other email encryption solutions have been designed with larger business in mind, which can afford the burdensome infrastructure costs associated with procuring, installing, supporting and maintaining these enterprise solutions.
How Do I Open a .ML256 File?Download the Free  MessageLock Decryptor
Download MessageLock free decrytor
Requirements: Windows 2000/XP/Vista/Seven .Net Framework 2.0
What is MessageLock Decryptor?
Has someone sent you a file that has the extension .ML256? To open this file, you will need two things: 1. the password, 2.MessageLock Decryptor software.
MessageLock Decryptor is a free Windows software program that lets you open files that have been encrypted by MessageLock. These files have .ML256 as their file extension, and are protected by 256-bit AES encryption.
MessageLock Decryptor can only decrypt .ml256 files, and it will not encrypt files.
Note to MessageLock Customers If you have installed MessageLock, then you do not need MessageLock Decryptor on your computer. To encrypt a file so that it is compatible with MessageLock Decryptor, select the "ML256" encryption method in MessageLock's "Manage Passwords" page. You may distribute MessageLock Decryptor to others.
How does MessageLock Decryptor Work?
After installing MessageLock Decryptor, just click on a .ML256 file. Windows will pass the file directly to MessageLock Decryptor, and you will be prompted for a password.
How to open .ml256 file
Input File is the path to the file you are opening. If you click on a .ml256 file, this is added automatically.
Output Directory is the location where MessageLock Decryptor will copy the decrypted files. The default is your Windows desktop, however, you can select any location you wish.
Is it Safe?
MessageLock Decryptor does not contain any spyware, adware, nor any tracking or registration mechanism. We do not keep any records of who downloads MessageLock Decrytor. This is a free software package published for the benefit of MessageLock users.
Please follow these guidelines when using MessageLock Decryptor:
1. If you do not know the person who sent you the .ML256 file, do not open it.
2. If the password was included in the email message, do not open the message.
3. Scan the decrypted files with your anti-virus software before opening.
How to Test MessageLock Decryptor?
To see if MessageLock Decryptor installed correctly, click here to download a .ML256 encrypted file. The Password is: Test123.
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