The Skype Web SDK requires that the Unified Communications Web API (UCWA) framework is installed and enabled on your Front-End, Edge and Director servers. If you're not already using UCWA, then you'll need to perform the following steps.
Step 1 – Upgrade Your Servers
Ensure that all your servers are running the latest Lync Server 2013 Cumulative Updates, or better still, Skype for Business 2015
The latest updates for Lync and Skype for Business can be found on Technet.
Important: All your Lync or Skype for Business services must be updated to the same update release. You will experience inconsistent behaviour and errors with mismatched updates.
Step 2 – "Boostrap" Your Servers
The Bootstrapper application, built into Lync 2013 and above, needs to be executed on each of the servers above. This can be performed using the command shown below.
<code class="bash">
%ProgramFiles%\Microsoft Lync Server 2013\Deployment\Bootstrapper.exe
</code>
Step 3 – Configure Trusted Connections - Cross Domain Authorization
You now need to tell your Lync or Skype for Business servers which domains to trust connections from. To do this, you simply use the Set-CsWebServiceConfiguration commandlet from a Lync or Skype Management Shell that has been started with Administrative privileges
<code class="bash">
$myurl = New-CsWebOrigin -Url "{https://mysite}"
Set-CsWebServiceConfiguration -Identity "{myidentity}" -CrossDomainAuthorizationList @{Add=$myurl}
</code>
Don't forget to replace 'mysite' with the fully qualified domain the web site on which you'll be using the Skype Web SDK. You should also replace 'myidentity' with something more relevant to your environment.
These steps must be performed on every Front-End, Edge and Director server you have.
Instructions for this can also be found in my Pluralsight course!
If you're not sure whether your domain has been added, you can use the Management Shell to query the list of authorized domains using the command below.
<code class="bash">
Get-CsWebServiceConfiguration | select -ExpandProperty CrossDomainAuthorizationList
</code>
