Mailservers and Groupware Solutions under your control

Email, calendar and contacts are basic functions that should continue to be available in a user-friendly and reliable manner.

Open standards and secure protocols

Software that implements IMAP, CalDAV, CardDAV and S/MIME correctly and works across vendors.

Complete control of your data

We operate your mail server - and deliver the entries for the data protection management system (DPMS) at the same time.

User-friendly and suitable for multiple environments

A good user experience across different operating systems, clients and mobile phones is of the utmost importance to us.

Modular and flexible

Full transparency and complete control over every component. No inflexible complete solutions and their legacy systems.


Effective protection against spam and ransomware.

Open source and open standards

There’s no need to be locked into a single vendor for email, group calendars, and enterprise-wide contact management. The standards IMAP (for mailboxes), CardDAV (contacts / vCards), CalDAV (calendars, tasks) and S/MIME (encryption) are sophisticated and well supported across the board. They can also be used reliably on mobile phones.

We have set ourselves the goal of creating standards-compliant, open-source-based groupware solutions for you - secure, flexible, modular and cost-efficient.

While other communication tools such as chats and video conferences may take centre stage in your internal communication, email remains a relevant channel for customer communication due to its direct, documented and universal nature.

Let’s talk about your environment


You are also welcome to directly send an email to or call us on +49 721 7540 7430 (Mon–Fri, 9:30 am–5 pm). Your data will only be used to process your request and not be transferred to any third party (as described in our privacy statement).

Modular approach

We use stable tried-and-tested individual components for each task. This allows us to respond to individual requests or improve developments in the future. You can find a selection of our preferred components below.

Server components

Client components

What we don’t (won’t) offer

No complete solutions such as Kopano or Zimbra

We do not implement complete groupware solutions like Kopano, Horde or Zimbra. In our opinion, these products lack modularity and flexibility.

Due to the lack of influence on single components, one has to live with partial weaknesses 2 in the overall solution, especially if these weaknesses have arisen historically or because compatibility with Microsoft Exchange is desired. 3 4 We consider them unsuitable, even if they are often available as open source or use the server components mentioned above, which are also used by foundata.

No Microsoft 365 / Exchange Online

We do not migrate to Microsoft 365. SaaS cloud solution does not deliver the best outcomes for our customers. The incompatibility of Exchange and Outlook with all other relevant clients and solutions places you at a high level of dependency, which could actually be avoided. This is further reinforced by Exchange Online and dovetailing with other Microsoft services.

The use of Microsoft 365 in companies where professional data protection is involved can also generate enormous effort and thus costs. Recording processing activities and legal bases, as well as the data protection impact assessment required in many environments prior to introduction, become very time-consuming. Furthermore, the legal basis for data transmission remains unresolved.

M365 Cloud Exit

As it so happens we do offer support for “M365 cloud exit”. If your company is considering this step our experts are here to help you migrate away from Microsoft 365 and build a customized, cost-effective and secure on-premise solution in its stead.

Exchange and Outlook with limitations

foundata relies on the strengths of open source, open standards and interoperability. Microsoft Exchange as well as Outlook generally break with these concepts and values.

Nevertheless, we are realists. Many companies have already invested in established technologies like Microsoft Exchange and Outlook or are tied to them because of other dependencies or industry software. This is why we continue to support these systems in existing environments. Our team has extensive and long-standing experience with Outlook4 and Exchange administration and customer environments in active support.

It should also be noted that Microsoft is making the operation of Exchange on-premises (i.e. hosted at your company) increasingly unattractive, especially with regard to licensing types and costs.5 Microsoft 365 and Exchange Online are clearly the strategic focus of Microsoft.

  1. K-9 Mail will transform into Thunderbird on Android ↩︎

  2. For example, Zimbra is functionally stable, well thought out and reliable, but in our experience the webmail interface has low user acceptance. If it were modular, this could easily be swapped out for a more appropriate interface. ↩︎

  3. For example, Kopano (formerly Zarafa) is attempting to reimplement the Microsoft MAPI protocol and stick to Outlook as the supported client. Furthermore, storing the actual emails in an RDBMS like MySQL is unwise in our opinion and mail servers like Dovecot use another method for a reason. ↩︎

  4. In environments with Outlook, we believe that Microsoft Exchange should be used on the server side to avoid problems. Furthermore, Microsoft Outlook is only able to handle CalDAV and CardDAV via third-party extensions such as CalDAVSynchronizer and is a mediocre IMAP client. Maintaining compatibility with Outlook breaks with many concepts. Therefore, we only support Outlook in connection with Microsoft Exchange. ↩︎ ↩︎

  5. See also Microsoft Exchange Server Roadmap Update June 02, 2022: “The next version will require Server and CAL licenses and will be accessible only to customers with Software Assurance, similar to the SharePoint Server and Project Server Subscription Editions.” ↩︎