Much like the Mi-Forms Client, there is a default location the Mi-Forms Server will search for non-embedded assemblies. These assemblies can include ones we provide you with the designer installation, or custom dll's created with .NET using Visual Studio. For a standard installation of the Mi-Forms Server, the default location is C:\Inetpub\wwwroot\MFS\script_assemblies. 

If you choose an alternate installation path during the initial setup of the Mi-Forms Server, the location will be the script_assemblies directory under your custom installation directory. 

This location can also be customized during form design by editing the Form Properties. To access this select File>Form Properties>Advanced and change the Script Assemblies Path as shown in the following photo:

The script_assemblies directory is not created as part of the installation as of version 7.0.1. You will need to create this directory manually.