This is generally an indication that the PDF file has been produced by scanning a document.
Check by performing a Select All, Copy and Paste to a text editor and/or check the Producer of the PDF by opening in Adobe and going to: File/Document_Properties/Description/PDF_Producer. Many times the Producer will indicate that it is a type of Image producing product.
Monarch cannot work with Image files. They need to be run through a third party OCR software product to convert to text.
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