Cleanup Global DataTypes Dialog Box
Use the Cleanup Global DataTypes dialog box to remove unused global data types from the XSD representation of the schema as you save the schema in BizTalk Editor.
To do this
Check boxes in the Unused Data Types list
Remove or leave the corresponding unused global data type from the XSD representation of the schema.
In general, your schema files will be smaller if they do not maintain information about unused global data types. However, if you intend to begin using a currently unused global data type again, you may want to leave that global data type in the schema.