Microsoft Exchange: What are the alternatives?

Companies can use Microsoft Exchange to manage all of their emails, appointments, and documents in one place, making it possible for large groups of employees to share access and work simultaneously on projects. At a time when mobility and flexibility are becoming increasingly important to the working world, programs like Exchange make it possible to collaborate easily and efficiently.


The new version Exchange 2019 includes additional features that can further improve your workflow.

The software works with Windows infrastructure, in particular with Outlook, and is among the most widely used groupware solutions. But that doesn’t mean that there are no alternatives to Microsoft Exchange. Depending on the structure and flexibility of your IT infrastructure, there might be products from other providers that are better suited to your needs. However, before deciding on an Exchange alternative, you should familiarise yourself with the pros and cons of the various software solutions.

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The pros and cons of Microsoft Exchange

Microsoft Exchange Server is most advantageous for small and medium-sized companies, since the servers can be rented externally, which eliminates the need for costly in-house IT infrastructure. Alternatively, your company can decide on an on-site solution for more control over their data, but will then have to take care of the servers itself (including cumulative updates, data administration, etc.). This is normally out of the question for smaller companies.

Using Microsoft products tends to be easy for most employees, thanks to Microsoft’s wide reach — Outlook is probably one of the best-known email clients worldwide. However, not every administrator finds maintaining the Exchange server ideal, which is why many IT experts look for alternatives to Exchange. This also has to do with the fact that Microsoft products come with licensing fees, and small businesses prefer to use free mail servers.


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Exchange Server Alternatives

There’s a reason Exchange is so popular. The software offers a variety of useful features and comprehensive administrative options. Yet for some users and administrators, it’s still not quite the right solution. Many users prefer, for example, open-source exchange servers or are looking for specific features.

OX App Suite

The OX App Suite (also called Open-Xchange) is an open-source groupware solution that’s well suited to mid-sized and large companies. It provides everything you need for collaboration, including email servers and other office programs. Word processors, spreadsheet software, and presentation software is available online, making it perfect for collaborating on projects. Address books and calendars can also be shared.

Companies can also take advantage of shared file storage. Individual team members each have their own folders, which can easily be shared with other users. The OX App Suite can be implemented in a variety of ways: You can use the service in the cloud or as a SaaS or host it on your own server. You can even use cloud storage and the email service in mobile apps. Everything else can be accessed using a browser.

Pros Cons
Many features  
Complete Office suite  
Partially usable in mobile apps  


Open-source with high security standards: The software Kolab is free and, if you have enough technical know-how, can be adapted to your specific needs. It was originally developed for the German Federal Office for Information Security, so it will come as no surprise that this Microsoft Exchange alternative places a premium on safety and data protection.

Anti-spam and anti-virus solutions are also included in the software. As with many of its other features, Kolab uses well-established open-source modules for these solutions, which are also implemented in other projects. Connections with other collaboration solutions such as OwnCloud also set Kolab apart.

Since Kolab is open-source, it can easily be installed in Linux. However, if you don’t want to install and configure this groupware solution on your own, it’s also possible to take advantage of the services of the company Kolab Enterprise. Then you’ll be able to access all its features in a hosted cloud.

Pros Cons
Connections with other tools  
High security standards  


Zimbra is also an open-source and free Exchange alternative. It boasts a strong email service, which the whole company can use to communicate. Users can access their inbox using the browser. Zimbra has all the features that you need for managing emails, calendars, contacts, and notes. In addition to the free version, users can choose to upgrade to a paid version. This is useful if you’d like to synchronise Zimbra accounts with email clients like Outlook.

However, even if you stick with the open-source version, you can take advantage of support for ActiveSync. This Microsoft app makes it possible to synchronise data on multiple devices.

Zimbra can be installed on various Linux distributions.

Pros Cons
Open-source Synchronisation with Outlook only possible in paid version
Comprehensive web features  

Kerio Connect

Kerio Technologies develops software solutions for companies and offers an Exchange alternative called Connect. Connect is a mail server that runs on Windows and MacOS as well as Linux, and can be implemented on-site or on a cloud. Another advantage of this software is its easy setup: Kerio claims that within just 20 minutes employees can start working with it.

The software’s instant messaging service sets it apart. Employees can use this feature to quickly exchange information with each other without having to write entire emails. Since the service runs with XMPP, software from other producers can also be used for the chat function. That’s also true of the email service: You can use different clients to access your emails or just use Kerio’s web app. In addition, Kerio Connect uses Microsoft ActiveSync to send messages to mobile devices.

Pros Cons
Easy setup Not open-source
Cross-platform capabilities  
Connections with software from other developers  

CommuniGate Pro

Another strong Microsoft Exchange alternative: CommuniGate Pro provides all the features needed for communication within a company. In addition to the email service, you can also share notes, calendars, and tasks with co-workers. Various client programs can be used to access the server’s functions, including Outlook, Thunderbird and Apple Mail. In addition, CommuniGate Pro offers its own web app, which includes various layouts and can easily be accessed in your browser.

Companies using CommuniGate Pro can also take advantage of VoIP and instant messaging. Small organisations can use the software for free. However, if you have a team of more than five people, you’ll need to buy a license.

Pros Cons
Cross-platform capabilities Only free for very small teams
Comprehensive web app Not open-source

Google Workspace

Google also offers an Exchange alternative. In Google Workspace, you’ll find all the tools you need for day-to-day office work. Many users are already familiar with Gmail and Google Docs. Google Hangouts is also included in the product suite, which allows teams to communicate even more effectively. Google Workspace brings is a paid-for service that bumps these features to a professional level. For example, it allows you to use your own email domain. Administrators are also given more options — they can manage access to certain functions, put together groups, and keep security restrictions up to date.

Google Workspace is designed to work with Google’s cloud. The advantage to this is that everything is set up perfectly and employees can work from anywhere and still have access to files. However, it’s not yet possible to run the program on your own server.

Pros Cons
Comprehensive portfolio Only available as SaaS
Partially available in mobile and desktop apps Not open-source

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All Microsoft Exchange alternatives at a glance

Whether you’re looking for an open-source or free Exchange alternative or want to buy all the necessary hardware right away, you’re sure to find the right solution for your team among our list of Exchange alternatives. The following table summarises the most important characteristics of these groupware providers.

  Open-source Anti-spam Security ActiveSync Mobile app Webmail What makes it special?
OX App Suite   Complete office solution
Kolab   High security standards
Zimbra   Comprehensive web app
Kerio Connect   Instant messaging
CommuniGate Plug-in   Cross-platform capabilities
Google Workspace   Complete office solution

Don’t need a complete email server for your team, but still need software to enable collaborative working? Collaboration tools can boost productivity and communication among employees.

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