Office Web Apps 2013 - Unhealthy

Ran into this issue on my lab servers.  I installed Office Web Apps 2013, configured it, all good!  But then Windows Update showed a patch from 1/2/14 for OWA, I applied that, and afterwards, Get-OfficeWebAppsMachine showed that my server was Unhealthy.

I did some Binging and found that indeed yes, there is a process to follow for patching an OWA server - first, remove the OWA server from the farm with Remove-OfficeWebAppsMachine, then apply the update, then use the New-OfficeWebAppsFarm again to rebuild the farm. 

Following a comment in a host here:  http://michaelvh.wordpress.com/2013/04/01/the-curious-health-problems-of-the-office-web-apps-server/

I enabled HTTP Activation for the WCF Services for the .Net Framework 4.5 on the OWA server.  Since I'm running Server 2012, I needed to use the Features option on Server Configuration to get this working:

 

 

Did a reboot for good measure, now Get-OfficeWebAppsMachine shows Healthy!