The Microsoft Outlook e-mail exchange client has a lot of useful features, but security is a major issue and can lead to virus traffic on the internet. Some free alternatives which give better security features and are simple e-mail facilitators, with complete Personal Information Managers (PIM's), including a planner, diary, calendar, etc. are PhoenixMail, Mozilla Thunderbird and Sea Monkey. These are open source and are available on the internet for free; they can also be modified as per your requirements. If you use Microsoft Outlook for scheduling, consider using Thunderbird as a reliable web e-mail replacement. IncrediMail, Pine, Pegasus, Netscape messenger and Calypso are pure e-mail clients, all of which are available on popular operating systems like Windows, Linux, Mac OS and Sun Solaris.
Outlook is a mail client allowing you to your read and send email by connecting to the server on which your account exists. This is done either by accessing your account via POP (Post Office Protocol) or having Outlook configured as an IMAP (Internet Message Access Protocol) client to retrieve your mail on an IMAP mail server. Among the various free mail clients available, you have Phoenix Mail and Thunderbird that can match Outlook Express for performance.
Free, open-source email application that can be adjusted for use on different operating systems.
Supports multiple mail accounts and provides an easy to use interface.
Free, open source email client providing features such as anti spamming filters and embedded RSS reader.
Supports multiple mail accounts and is easily customizable.