This guide with OJOsoft Total Video Converter as an example will show you how to add multiple files to video and audio products more than one time. With OJOsoft video and audio products, you can load multiple files from multiple folders to convert in batch mode.
After you loaded one or more files, you still want to load some more files. You can click + button.
Choose all files you want to add in the popup dialog, click Open button.
The file you chose is shown in the Input File Name list.