Indigo PDF provides the capability to edit or remove metadata from a PDF document, as well as add custom metadata entries. Here are the steps to change metadata in a PDF using Indigo PDF:

1. Open PDF for Metadata Changes:
   • Use the application’s file selection or upload feature to choose the PDF document for which you want to modify metadata.
2. Edit Metadata:
   • Indigo PDF allows you to edit specific metadata variables. You can edit or modify the following variables:
     • Author
     • Creation Date (in the format yyyy/MM/dd HH:mm:ss)
     • Creator
     • Keywords
     • Modification Date (in the format yyyy/MM/dd HH:mm:ss)
     • Producer
     • Subject
     • Title
     • Trapped
     • You can edit these variables as needed by inputting new values.
3. Delete All Metadata:
   • If you want to remove all metadata from the PDF, there is an option to delete all metadata.
4. Show Custom Metadata:
   • You can view the existing custom metadata entries associated with the PDF. These may vary depending on the document.
5. Add Custom Metadata Entries:
   • If you wish to add custom metadata entries to the PDF, you can do so by inputting the desired metadata values.
6. Apply Changes:
   • After editing, deleting, or adding metadata entries, click the “Change” or “Apply Changes” button to save the changes to the PDF’s metadata.
7. Download the Modified PDF:
   • Once the changes are applied, you will be prompted to download the modified PDF document. Choose a destination folder on your computer to save the updated PDF with the new metadata.
8. Confirmation:
   • You will receive confirmation that the metadata changes have been successfully applied to the PDF, and you can access the updated document with the modified metadata.

By following these steps, you can easily edit, delete, or add custom metadata to a PDF using Indigo PDF. This is helpful for maintaining accurate and relevant metadata information within your documents.