Getting Internal Server Error for OCR API

That's a generic error.  The OCR is bad at returning the exact error.  If you try to "Split" the document, I've learned it returns a better error for exactly what it doesn't like about the document.  For me I've been getting that error when I try to OCR a document that was digitially signed through docusign and has digital certificates.  That error sometimes comes for completely unknown reasons.  I have my OCR step in a loop where if it fails the first time I split the document and try again.  It either works the second time or the split gives me a better message.  This leads to the frustration of splitting a document on a number of pages (50) that exceeds the number of pages in the document.  This causes the Split API to throw an exception.

This seems quite rude since Adobe doesn't give us the ability to know the number of pages ahead of time.  They don't tell us the page count then throw exceptions for exceeding the page count.  If I ask to split a 20 page document on 50 pages, just return the 20 pages without error... or better yet give me a way to tell the page count.

Can you share the PDF in question?