Question: I am receiving the following error during a PDF import. What does it mean?

Here is what my PDF looks like:
 

Answer: This is a rare error, but it may point at something corrupt inside a PDF sheet. We have resolved it by deleting unnecessary content such as legends, words, and details in the sheet using a PDF editor like Bluebeam Revu or PDF-XChange editor. 

In the case of the PDF file above, deleting everything outside the Floor plan has resolved the problem:

It is essential to check for other PDF inaccuracies inside your PDF file, such as raster images inside a vectored plan, as is explained in the linked article

Related Articles

PDF inaccuracies from CAD files
Cannot import PDF into a Tekla Structures model
PDF