Although VBA edit does provide loads of libraries inherently, still, we may need to use few libraries which are not included by default. For example, For using Scripting.Dictionary object, or FileSystem object to search the fileSystem in an organized way, we need to add a reference to Microsoft.Scripting.Runtime.
Adding a reference purely means to instruct the VBA Compiler/Editor to include the functionality of a particular library so that we can use the functions available in the added library.
If you try to create a FileSystemObject, and write the following code:
Dim dictionary_ as Scripting.Dictionary
If we try to compile or run the code with out adding the reference it will show us the following error :
Add the reference to Microsoft.Scripting.Runtime as shown in the picture below. Go to Tools --> Reference --> Look for Microsoft.Scripting.Runtime. If you are unable to find it in the options, then you will need to browse for scrrun.dll.