A PowerShell front end to the MailKit project including a near-drop-in replacement for Send-MailMessage
If you've used Send-MailMessage recently, you've likely seen this error message:
If you go to the link for more information, it will let you know that Net.Mail.SmtpClient (which Send-MailMessage is based on) does not support many modern (and more secure) protocols. The recommendation is to use MailKit instead.
Unfortunately, this doesn't help much if you're using PowerShell instead of C#, unless you're wanting to import this type library into your scripts and build emails manually, which isn't a great experience when you're used to Send-MailMessage doing that for you.
This project was started to build a better replacement for Send-MailMessage based on MailKit to address the shortcomings of current replacements available. Send-MKMailMessage was built first-and-foremost to replicate all existing functionality of Send-MailMessage using MailKit as its basis, and to do so by taking the same parameter input as Send-MailMessage: if you're using Send-MailMessage, no matter what way you're using it, you should be able to just change the call to Send-MKMailMessage and have it work the exact same way. At most, you should only have to add a -Legacy switch to ensure backwards compatibility with Send-MailMessage.
As there are improvements available in MailKit, and some of them are at least somewhat incompatible with the way Send-MailMessage accepts input, there are some parameters that have been deprecated into a "Legacy mode" with Modern counterparts, and the new cmdlet behaves differently in a few spots by default in "Modern mode". For example, it defaults to attempting SSL/TLS connections, where Send-MailMessage would only do so if you explicitly told it to.
At this time, Send-MKMailMessage is the only cmdlet that has been built, but the goal is to add additional tools to the project for other mail tasks made possible by MailKit.
Additionally, the first version of PoshMailKit is built on .NET Framework 4.8 to support use in Windows PowerShell 5.1, but future versions will likely be based on .NET 6.0+ and likely will not be available to Windows PowerShell at all; that said, if that is the direction this goes in, version 1.x will be maintained for some period of time for PS 5 support; it just won't get any new cmdlets.
You can find the current version on the PowerShell Gallery here: https://www.powershellgallery.com/packages/PoshMailKit/
You can also install using the following command:
Install-Module -Name PoshMailKit -AllowPrereleaseThis is built in Visual Studio 2022 using C# 7 (Framework 4.8). It relies on MailKit, System.Management.Automation.dll (version 10.0.10586; deprecated but needed to target Windows PowerShell rather than just modern PowerShell), and System.IO.Abstractions (for unit testing with a mock filesystem), as well as the dependencies of those packages.
The unit test project relies on MailKit, System.IO.Abstractions, System.IO.Abstractions.TestingHelpers, xunit, and Moq.
Everything should install either automatically or through the NuGet package manager when loaded in VS 2022.