Several days ago, Jared raised a Pull Request for Posh-SYSLOG to correct an issue with the module’s manifest. It seems that in version 3.0 of Posh-SYSLOG, I used the PowerShellHostVersion attribute of the module manifest and not PowerShellVersion to specify the minimum Powershell version. This wouldn't have created issues within a normal PowerShell session, but would have prevented the module from loading in VS Code (as Jared reported) or the ISE.