If you are trying to open a PDF document in the Preview pane, and it either does not load, or you see a download prompt like this:
"Do you want to open or save [file name] from view.netdocuments.com?"
1) You should first go to Settings > Application Settings. Uncheck the box for PDF Viewing.
2) If that does not work, then in Adobe, go to Edit > Preferences > Internet and look under the Web Browser Options you will need to make sure you have it set to "allow web viewing."
3) In Internet Explorer, go to Tools > Manage Add-ons and make sure the "Adobe PDF Reader" add-on is enabled.
If you are using Chrome you may also need to go to Settings > Content Settings > PDF Document to make sure that the "Chrome PDF Viewer" is enabled.
4) If that still does not resolve it, then you will need to either reset your browser or re-install Adobe.
NOTE: With Nuance, there is an option to install the integration with IE. Some customers have reported problems viewing PDFs in IE when using Nuance, but with version 8.2 of Nuance this seems to work properly.