Outlook is, hands-down, the most popular email client among the business set. And with good reason. It connects to Exchange, which allows businesses to determine many aspects of how and what their users can manage, use, and control. It also allows the sharing of things like calendars and contacts. But not all businesses (especially small businesses) employ Exchange. For them, there are plenty of alternatives to Outlook. Even businesses that do have Exchange may use an alternative to connect to a groupware server. Let’s take a look at a few of these alternatives and see what they have to offer.

Top Microsoft Outlook Alternatives

Note: This list is also available as a photo gallery.

1: Thunderbird

Thunderbird is one of the best of the alternative email clients. It benefits from the strength of Firefox, provides plenty of add-ons, includes a great migration assistant, offers a powerful address book, makes use of an attachment reminder, and has plenty of built in security features. Thunderbird is also one of the more stable email clients available, and it’s cross platform. With its user-friendly tabbed interface, Thunderbird makes working within the realm of digital communications simple. Plus, it is possible to connect Thunderbird to Exchange.

2: Zimbra Desktop

Zimbra Desktop is a unique take on the desktop email client. Although you won’t be connecting Zimbra to an Exchange server with ease (there are reports that it is possible, though), you can connect Zimbra to a host of other services. One feature that sets Zimbra apart is its ability to connect to social networking sites, such as Facebook and Twitter. Zimbra can connect to Mail, Hotmail, Gmail, Yahoo, and a number of other third-party email hosts. The interface takes getting used to, but once you “get” Zimbra, you’ll find it quite powerful and useful.

3: Claws Mail

Claws Mail is simply one of the fastest, most configurable email clients available. Now you won’t be connecting Claws Mail to an NTLM-based Exchange server any time soon (or maybe ever). But if you don’t need Exchange support and you’re looking for an alternative email client that can do just about anything else, Claws might be one of your best solutions. With a good number of plug-ins, an incredible configuration tool, one of the fastest start times of any email client, multiple MH folder support, Mbox import/export, external editor, built-in GnuPG support, and support for SSL over POP3, SMTP, IMAP4rev1, and NNTP protocols, Claws Mail makes any power user happy. But it’s not just for power users. With its easy-to-use interface, it can also satisfy the new user.

4: eM Client

eM Client is fully optimized to run on Windows XP, Vista, and Windows 7. It can connect to third-party POP/IMAP servers like Hotmail, Yahoo, and Gmail and import from other email clients, and it offers a full-featured calendar that can even sync your Gmail calendar or your mobile device. Messages can be tagged, searched, and easily filtered with an interface that’s easy to navigate. eM Client also contains a powerful tool that lets you share contacts with other users, and it can Sync your Google contacts. You won’t be connecting eM Client to Exchange, but you will enjoy a feature-rich, easy- to-use email client.

5: Pegasus Mail

Being one of the oldest email clients on the block has its advantages. Pegasus Mail offers an incredibly rich community and a stability not found in other clients. And unlike some other email clients, Pegasus Mail has a rigid adherence to standards. One of the most impressive claims from Pegasus Mail is that it will protect you from even the worst HTML-borne viruses and exploits. That is a bold claim, but one it can back up. Pegasus Mail can’t connect to Exchange. But if you don’t use Exchange and you want an email client that will help prevent infection from HTML-mail sources, Pegasus Mail might well be the solution.

Your picks

If you’re exploring Outlook alternatives, give the above clients a try. Although not every client will connect with Exchange, they make up for it in flexibility, reliability, and security.

What Outlook replacements have you used? Are there any you would definitely add to (or exclude from) this list?

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