Hi there, long time lurker (this forum has helped LOTS!) first time poster.
Using: Infopath 2013 filler, C# code, mixture of Windows 7 & 8 machines.
One of my views has a button to export the view as an mht file using a simple line of code:
this.CurrentView.Export(path, ExportFormat.Mht);
This works absolutely fine for everyone ...