After configuring my SharePoint 2013 Farm and also configuring Office Web Apps 2013 I had created the binding between the two farms, but I was not getting at ‘Previews’ come up when I was clicking on the “…” icon next to a document.  I was also not seeing any preview when viewing Search Results either.  The answer was very simple in the end.

By running the Powershell command :

Get-SPWOPIZone

I found that my zone was set to internal-https.  When I ran the cmdlet:

Get-SPWOPIBinding

I saw that the zones of each of the document types were set to external-https.  I assumed that the zones should match so I then ran the cmdlet:

Set-SPWOPIZone –zone “external-https”

I then refreshed the browser page and up came the Office Web Apps preview, and documents were also opening in the browser.  If you get this issue then make sure you follow the instructions in the following TechNet  article, which being a bloke I only read fully after I’d attempted a manly install by myself …  http://technet.microsoft.com/en-us/library/ff431687.aspx

Cheers

Dave Mc