I've been using Kolab [0] for years for self hosting the email, calendar and tasks. There is an official integration with Seafile which gives you a "Google Driv

I've been using Kolab [0] for years for self hosting the email, calendar and tasks. There is an official integration with Seafile which gives you a "Google Drive"/"One Drive" experience (you can also integrate it with NextCloud), while recently there's been Libre Office integration available which gives you word processing, spreadsheets and presentations in your browser; I'm also using it. The overall experience is not as smooth as with Google or MS, but I do have Exchange protocol, file storage with management and online document editing and it works. First time it took me almost two weeks to setup everything, but I've been doing the same setup for my friends, for their small to mid sized companies for less than a week. Their main website is not managed well but they have a pretty active development community, very useful mailing list (you can browse the archive) and somewhat dated documentation but the changes are not that hard to figure out. Once everything is set, the update process and maintenance are almost automatic through the native linux package manager. [0] https://www.kolab.org/ https://www.kolab.org/