The .NET-Framework allows you to have an EXE assembly reference another EXE. When the main EXE creates a class in the referenced EXE, the second EXE is loaded in the same AppDomain as the main EXE.
.NET projects generated by VB Migration Partner don’t support this feature, though, at least not fully. A converted .NET program can reference a compiled assembly with EXE extension, but several features may not work as expected. For example, all such EXEs share one single instance of system-level objects, which means that the Forms6 collection includes only the forms opened by the main EXE and not those opened by the referenced EXE.
Please notice that the VB Migration Partner Team can’t offer support for migrated applications that reference external EXE assemblies.