A dialogue box should appear on screen. Next to 'Opens with' click on "Change..." and then select the application of your choice.
Note: This may be Adobe Reader or Foxit Reader depending on your organizations or personal preferences.
If you have a paid subscription to Adobe Acrobat or Foxit Editor, make sure to select that instead.
Press OK on the list window and then OK on the properties dialogue window. This change will take place to all PDF files being opened from your web browser, local disk, DropBox, OneDrive, SharePoint and email attachments.