Gpg4win - is a security software program that can encrypt and attach digital signatures to your emails and files when uploading or sending them online, in order to prevent unauthorized users from accessing your private information.
Aside from the main application, you may install a key manager for OpenPGP, X.509 and common crypto dialogs (Kleopatra), GNU privacy assistance (GPA), an Outlook plugin (GpgOL), shell extension (GpgEX) and a Claws mail-user agent (Claws-Mail).
The interface of the utility is represented by a standard window with a well-defined layout. Gpg4win supports a wide range of certificate types, including ASC, CER, CERT, DER and PEM.
You can either import them from the computer or create your own one - a personal OpenPGP key pair or X.509 key pair and certification request.
All you have to do is specify a name, email address, comment, as well as configure advanced settings when it comes to the key material (RSA or DSA) and certificate usage (e.g. signing, encryption, validity, authentication). Once you enter a password phrase and write text to be used as inter-character timing, you can create the certificate.
So, you can send the certificate via email, upload it to a directory service or create a backup, as well as view lists of your personal, trusted and other certificates, look them up on a server and use a search function when dealing with large amounts of data. Other features of Gpg4win let you create and verify checksum files, import Certificate Revocation Lists, perform a self-test, as well as configure toolbars and shortcuts.
The application runs on a moderate quantity of CPU and system memory, has a good response time and includes user documentation. No error dialogs have been shown in our tests and the program did not hang or crash. All in all, Gpg4win supplies users with the necessary means to create, import and attach certificates to emails.
Download: 
Gpg4win.4.2.0.exe - 33.3 MB