It was not. I had used your earlier instructions:
" <appSettings>
...
<add key="ConnectionString" value="server=(local)\portal;database=SamplePortal;uid=test;pwd=test"/>
<add key="CuteChat.ConnectionStringProvider" value="SamplePortal.ConnectionStringProvider,SamplePortal"/>
</appSettings> "
I changed it back to your latest instructions and it still produces the same error.
What should the value be? Is it <database>.ConnectionStringProvider,<database> or is "CuteChatControls" or "SamplePortal" arbitrary values?