Question: can irfanview open pdf files?
Answer: POSTSCRIPT - (version 4.54): allows IrfanView to read EPS/PS/PDF files (using Ghostscript, take the 32-bit (!) EXE installer, like "gs926w32.exe") or Ghostscript 64-bit for IrfanView 64-bit (like "gs926w64.exe").