While testing a new service I was creating on my BizTalk development machine, I wanted to test the service using the WCF Test Client.
However, when I brought up the tool, I was shown all of the adapters that are created for the WCF LOB adapters: SAP/SQL/ and the two Oracle adapters.
You can comment out the adapters so you don’t see the red x’s in the the tool

By going into the machine.config in the (for me) C:\Windows\Microsoft.NET\Framework\v4.0.30319\Config folder and commenting the endpoint from the client section

<client>
      <endpoint binding="sqlBinding" contract="IMetadataExchange" name="mssql"/>
      <metadata>...
      </metadata>
</client>

to

<client>
      <!--<endpoint binding="sqlBinding" contract="IMetadataExchange" name="mssql"/>-->
      <metadata>...
      </metadata>
</client>

I don’t see the the red x, however, if you don’t have the required assemblies (Oracle, SAP, etc) the tool will close automatically without giving you any results.

Lesson learned: only install the adapters that you will be connecting to, otherwise, the WCF Test Client Tool will close miserably.