If you own an Apple computer and have problems viewing PDF files, don’t think those PDF files are corrupt. You have probably just upgraded to the Mountain Lion OS X operating system.
People started reporting strange Mountain Lion activities after upgrading their Apple systems to Mountain Lion OS X. Many strange happenings seemingly unrelated to PDF viewing were observed.
For instance, wheresdavid reports in the Apple Support forum:
…my cursor has changed from an arrow to “cross hairs.” This oocurs not only in safari but other programs. sometimes it’s an arrow sometimes it’s a cross hair. For example, in this forum when I move the cursor over the tabs “store” “mac” “ipod” “iphone” etc sometimes the cursor is an arrow and then it changes to cross hairs. In the body of the page it is always a cross hair even when i scroll over hyperlinks. I’ve restarted my computer a few times and sometimes the arrow comes back – but only for a short period of time and then it’s back to the cross hairs which I find quite annoying.
Other people reported problems with the cursor changing in Microsoft Office applications. Some Mac owners have reported other problems after upgrading to the Mountain Lion OS X. They see black browser screens when they attempt to view PDF files.
Here is how to fix your misbehaving Mountain Lion OS X installation. The problems reside in incompatible Adobe plug-ins. The little miscreants are called AdobePDFView.plugin and AdobePDFViewNPAPI.plugin.
Just navigate your way to the folder named /Macintosh HD/Library/Internet Plug-Ins/ and find these two files. Manually uninstall these files.
Next, you will need to go to the Adobe web site and install the OS X compatible Adobe Reader.