Office Web Apps Server 2013 - machines reported as Unhealthy

After you configure Web Apps 2013 farm you found the Web Apps Machine is Unhealthy

In order for IIS to understand .svc files, and not use the Static file handler, you need to install HTTP Activation for .NET Framework 4.5 WCF Services on your WAC machines. It can be done using the following PowerShell command:

Add-WindowsFeature NET-WCF-HTTP-Activation45

 

 

Once the feature is installed, there is no need for any server restart, you should see that your machines are reported as Healthy. Remember it can take up to 10-20 minutes. You can sometimes speed up the health reporting a bit by restarting the WAC Service:

 

Restart-Service WACSM

Ref: http://www.wictorwilen.se/office-web-apps-server-2013---machines-are-always-reported-as-unhealthy