It looks like the extension .pdf is not regognized anymore. It shows only raw text in the browser window...
Right or control click a PDF file you have saved on the hard drive then click: Get Ino
In the Get Info window you'll see: Open with
Select Preview from the pop up menu.
That isen't the problem. Problem apears just in Safari 7 as soon as you click on a pdf link.
Try this solution it works for me
The solution was: 10.9.1.
Retrieving data ...