smtp4dev Files

The fake smtp email server for development and testing

This is an exact mirror of the smtp4dev project, hosted at https://github.com/rnwood/smtp4dev. SourceForge is not affiliated with smtp4dev. For more information, see the SourceForge Open Source Mirror Directory.

The interactive file manager requires Javascript. Please enable it or use sftp or scp.
You may still browse the files here.

Name	Modified	Size	InfoDownloads / Week
Parent folder
Rnwood.Smtp4dev-win-x64-3.10.1.zip	2025-09-14	61.8 MB	0
Rnwood.Smtp4dev.Desktop-win-x64-3.10.1.zip	2025-09-14	110.3 MB	0
Rnwood.Smtp4dev-win-arm64-3.10.1.zip	2025-09-14	60.2 MB	2
Rnwood.Smtp4dev-noruntime-3.10.1.zip	2025-09-14	37.0 MB	0
Rnwood.Smtp4dev-linux-x64-3.10.1.zip	2025-09-14	60.8 MB	0
Rnwood.Smtp4dev-linux-musl-x64-3.10.1.zip	2025-09-14	60.8 MB	0
Rnwood.Smtp4dev-linux-arm-3.10.1.zip	2025-09-14	59.4 MB	0
3.10.1 source code.tar.gz	2025-09-14	1.5 MB	0
3.10.1 source code.zip	2025-09-14	2.0 MB	0
README.md	2025-09-14	1.9 kB	0
Totals: 10 Items		453.6 MB	2

See full installation instructions and options

File Name	Description
Winget package	Rnwood.Smtp4dev.Desktop Winget package (recommended easy option for Win10/11)
Winget package	Rnwood.Smtp4dev Winget package Win10/11)
Rnwood.Smtp4dev-win-x64-3.10.1.zip	Windows x64 binary standalone - Server edition
Rnwood.Smtp4dev.Desktop-win-x64-3.10.1.zip	Windows x64 binary standalone - Desktop app edition.
Rnwood.Smtp4dev-win-arm64-3.10.1.zip	Windows ARM 62-bit binary standalone
Rnwood.Smtp4dev-linux-x64-3.10.1.zip	Linux x64 (Intel 64 bit) binary standalone
Rnwood.Smtp4dev-linux-musl-x64-3.10.1.zip	Linux MUSL x64 binary standalone for Linux distros using MUSL libc
Rnwood.Smtp4dev-noruntime-3.10.1.zip	Architecture independent version. Should run on any platform where the .NET 8.0 (or greater) runtime is installed
Docker images for Windows and Linux - How to use Docker image
.NET tool Rnwood.Smtp4dev 3.10.1	.NET tool (recommended option for Mac OS) - How to use dotnet tool

Source: README.md, updated 2025-09-14

Other Useful Business Software

MongoDB Atlas runs apps anywhere Icon

MongoDB Atlas runs apps anywhere

Deploy in 115+ regions with the modern database for every enterprise.

MongoDB Atlas gives you the freedom to build and run modern applications anywhere—across AWS, Azure, and Google Cloud. With global availability in over 115 regions, Atlas lets you deploy close to your users, meet compliance needs, and scale with confidence across any geography.

Start Free

Get the most trusted enterprise browser Icon

Get the most trusted enterprise browser

Advanced built-in security helps IT prevent breaches before they happen

Defend against security incidents with Chrome Enterprise. Create customizable controls, manage extensions and set proactive alerts to keep your data and employees protected without slowing down productivity.

Download Chrome

Recommended Projects

Origami SMTP
Origami is a Fake SMTP server that features TLS support. It is platform independent, can read HTML emails, and can be customized.
spamhole - The Fake Open SMTP Relay
spamhole is a fake sopen SMTP relay, intended to stop (some) spam by convincing spammers that it is delivering spam messages for them, when in fact it is not.
MailHog
Inspired by MailCatcher, easier to install. Built with Go, MailHog runs without installation on multiple platforms. Run it from Docker Hub or using the provided Dockerfile. The SMTP server starts on port 1025, the HTTP server starts on port 8025, in-memory message storage. ESMTP server...
SMTP Test Suite
Simple SMTP Client and Server for testing the network configuration, firewall settings etc. The Client can send email to any standard servers (local SMTP, Gmail...). The Server will simply accept and show every incoming SMTP communication.
GPGrelay
GPGrelay is a small email-relaying server that uses GnuPG (the GNU Privacy Guard) to sign/encrypt (SMTP-Relay) or verify/decrypt (POP3-/IMAP-Relay) emails. This enables many email-clients to send and receive emails that are PGP-MIME conform.