First, you’ll have to get yourself a personal e-mail certificate, which is the cornerstone of any e-mail encryption scheme, and guarantees the authenticity of messages that you send. You can get a free e-mail certificate at Thawte.com (http://www.thawte.com/secure-email/personal-email-certificates/index. html).

After you sign up, you’ll receive a verification e-mail message to which you must respond. In the process of verifying, you choose the e-mail program you wish to use, and you’ll be given brief instructions on how. You then download the file onto your PC and import it into your e-mail program, which should have further instructions for installation and use.

Both you and your recipient must have certificates in order to exchange encrypted e-mail messages. Once set up, however, it’s a simple one-click affair to send an encrypted e-mail message.

Q: How can I password-protect files on my PC?

A: Password-protection of files can sometimes be done at the application level.

In Microsoft Word, for example, you can require that a password be used to open a file. In the Tool menus, select Options, and then from the Security tab in the Options dialog box, supply a password in the “Password to open” box. Consult the Help file of other mainstream applications for similar tools.

Of course, you might want to password-protect other kinds of files, too. One way is to use a file compression utility such as WinZip, and assign a password to the resulting zip file. Or you could enlist the help of a third-party utility that will encrypt files and folders for you. AxCrypt (http://www.axantum.com/AxCrypt) is free, available in 10 languages, and after installation allows you to right-click a file and encrypt it immediately.