ExaminePDF index is empty on Umbraco site after rebuilding indexes

Does anyone know how to configure the ExaminePDF index to pickup PDF documents off the media library in Umbraco. I try to rebuild the index, but no PDF documents are contained within it.

I believe I have got the search working off the index, but I can't test it without some documents being included in the index.

We currently store PDF documents in the media library in Azure and can find them in the backoffice (for background information).

This was due to the way the PDF's had been imported into Umbraco from Azure. In order for the index to pick up the PDF's each file type in Umbraco has a Type field which has to be PDF. In this case the files hadn't imported correctly so the type field was blank which would explain why they were not included in the index.