SHAREPOINT 2013 , CONTROL WHETHER PDFS OPEN IN WORD WEB APP OR THE DEFAULT PDF READER

Background:

When users open a PDF file from a SharePoint document library that uses Office Web Apps Server, the default behavior is to open the PDF in Word Web App. If this isn’t the behavior you want, or if your users are having trouble opening PDFs on smartphones, you can use Windows PowerShell commands to make PDFs open in your default PDF reader instead.

The following command will fix the situation, where PDF documents will always open in the default PDF reader, but previewing won’t work anymore

Get-SPWOPIBinding –Application “WordPDF” | Remove-SPWOPIBinding -Confirm:$false

The following fixed all my problems  Your PDF documents will be opened in the default PDF reader, the preview will work and Word Web App will present the PDF documents in the “embedview”.

Get-SPWOPIBinding -Action “embedview” -Application “WordPdf”| Set-SPWOPIBinding –DefaultAction

If you change your mind and later want to have PDFs open in Word Web App again.:

Get-SPWOPIBinding –Application "WordPDF" | Remove-SPWOPIBinding -Confirm:$false

New-SPWOPIBinding –ServerName "Server.corp.Contoso.com" –Application "WordPDF" -AllowHTTP

Note : At times it would be a browser setting as well.

1. Open Internet Explorer, and choose Tools > Manage Add-ons.
2. Under Add-on Types, select Toolbars and Extensions.
3. In the Show menu, select All Add-ons.
4. In the list of add-ons, select Adobe PDF Reader.
5. Click the Enable or Disable button (it toggles depending on the status of the selected add-on):

• Enable sets the Adobe PDF Reader add-on to open PDFs in the browser.
• Disable turns off the add-on so it does not open PDFs in the browser. 

References

https://blogs.technet.microsoft.com/office_resource_kit/2013/07/31/control-whether-pdfs-open-in-word-web-app-or-the-default-pdf-reader/
https://helpx.adobe.com/acrobat/using/display-pdf-in-browser.html