Recent changes to Safari and Apple are incompatible with the Acrobat plug-in.
Try the following fix: On an Apple laptop or desktop, remove the file called "PDFViewer.plugin" from the Library/Internet Plug-Ins folder.
Try the following fix: On an Apple laptop or desktop, remove the file called "PDFViewer.plugin" from the Library/Internet Plug-Ins folder.
Also, see the following links for further help:
http://helpx.adobe.com/acrobat/kb/pdfs-safari-acrobat-8-mac.html
http://www.tuaw.com/2012/10/29/cant-save-pdf-files-from-safari-with-mountain-lion-heres-the/