All of a sudden across various sites, almost 50% of all new Discover client roll-outs are completing successfully, but the "Discover.Designer.Desktop.exe.config" file is incomplete and contains none of the SIMS or Discover server/database information meaning Discover won't run until this info is manually put in. The Discover channel in SOLUS3 is set up correctly and nothing in SOLUS3 has changed and previous roll outs have worked a treat so why has this started to happen? It's these 6 rows that are affected and appear like this when the client has been installed:

<add key="authenticationServer" value=""/>
<add key="authenticationDatabase" value=""/>
<add key="interactiveLogonAuthenticationPrefix" value="_"/>
<add key="discoverInstance" value=""/>
<add key="discoverDatabase" value=""/>
<add key="sessionTimeout" value="-1"/>

What could be causing this? there has been no new Discover update, no SOLUS3 update so it's got me baffled! Anyone else experiencing this?