To run this script
Select Script → Schematic → Remove_Space_from_Schematic_Names from the Menus.
Or in Version 13 or higher you can run the utility directly from this page using this button.
This script will replace spaces in schematic names loaded in the project with underscores. Some processes on computers are not tolerant of spaces in filenames, such as exporting layouts, etc. This script will automate removing any spaces in schematic names.