Based on the screenshot it seems to rely on .NET 4.0. Is this still installed? Yes, it's still installed
Was there a new version of .NET installed or update with the trial install? Not that I'm aware of. Currently running .NET Framework 4.8. Shows installed. Have attempted to reinstall 3.5 through 4.8 and has no effect on the issue.
I get the same .NET Framework error when trying to run Lansweeper_start.ext. included a screenshot from Event Viewer as well as the error when trying to run lansweeper