Issue when creating pdf file while running knit, output file does not exist (knit-HTML is fine)

[mara]

See suggestions in the thread here:

New problems producing pdf from Rmarkdown

The "official" answer is here: https://github.com/rstudio/rmarkdown/issues/1285#issuecomment-374340175 Personally I don't recommend downgrading to rmarkdown 1.8.