Gpg4win is a installer package for Windows (95/98/ME/2000/XP/2003) with computer programs and handbooks for EMail and file encryption. Gpg4win and the software included with Gpg4win are Free Software.
You can choose all or some of the following modules during installation:

GnuPG: The core; this is the actual encryption tool
WinPT: A key manager and helper for various encryption matters
GPA: Another key manager, tasts are simply different
GPGol: A plugin for Microsoft Outlook 2003 (email encryption)
GPGee: A plugin for Microsoft Explorer (file encryption)
Sylpheed-Claws: A complete email program including the plugin for GnuPG