NeutronMail
Mailpile
Horde
Mailo
HEY
Soverin
Cypht
Teknik Mail
Zimbra
iRedMail
Roundcube
mailcow
Thunderbird
Microsoft Exchange Server
Postfix
Microsoft Outlook
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NeutronMailBased on our record, NeutronMail seems to be more popular. It has been mentiond 8 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
PS: I hope that we selfhosters will have a modern, efficient, easy to use mail suite one day with modern features like JMAP, good self-learning spam integration, automated checks and validations for SPF/DMARC/DKIM or whether the IP/host suddenly appears in a blocklist and integrated encryption at rest for emails. Something that isn't 30 services in a container image, with 30 different configuration styles. Maybe... Source: about 1 year ago
A bit related: there was a FOSS backend once but I don't think anyone wants to push further. Source: over 1 year ago
Some folks once started neutron which is an email server that can be used with the FOSS Protonmail web client but it was abandoned. And I guess you'd want to support JMAP in addition to IMAP as well apart from having automated encryption of incoming plain-text emails. Source: over 1 year ago
Anyway, to the topic: there was once neutron which is a server that aimed at ProtonMail compatibility. So that'd would simply would be able to use the same open source frontend from ProtonMail. However, this was abandoned. So you, or somebody else, could revive it. Source: almost 2 years ago
Some folks also started implementing an FOSS ProtonMail but this project was abandoned at some point. But maybe someone will fork and revive it one day. Source: almost 2 years ago
Mailpile - Mailpile is a modern, fast web-mail client with user-friendly encryption and privacy features.
iRedMail - A fully fledged, free email server solution, an open source project (GPL v2).
Horde - Horde Groupware is a free, enterprise ready, browser based collaboration suite.
Roundcube - Web-based IMAP email client
Mailo - Mailo is an email client where you can send and receive emails to and from anyone with an email address.
mailcow - An open source mailserver suite.
