If filenames are missing in your Photoshop Elements catalog, it usually indicates that files have been moved, renamed, or deleted outside the Elements Organizer, causing the catalog to lose track of them. To fix this, reconnect the missing files to update the catalog with their current locations:

1. Open Elements Organizer.
2. Select the files with the missing file icon or choose File > Reconnect > All Missing Files to reconnect all missing items.
3. If you know the new location of the files, click Browse and navigate to the folder containing the missing files.
4. Select the missing files in the dialog box. Use Shift-click or Ctrl/Cmd-click to select multiple files.
5. Click Reconnect to update the catalog.

If the catalog is damaged or you encounter errors, use the Repair function in the Catalog Manager:

1. Close Photoshop Elements and Premiere Elements.
2. Open Elements Organizer and go to File > Manage Catalogs.
3. Select your catalog and click Repair.
4. If no errors are found, click Repair Anyway or choose to delete and regenerate the thumbnail cache if prompted.

Ensure your user account has sufficient permissions to read and write files in the catalog folder by checking the catalog location under Help > System Info.

These steps help restore the catalog's connection to your files and fix missing filename issues. For detailed troubleshooting, see the Elements Organizer troubleshooting guide and Photoshop Elements catalog backup and repair.