c# error:Unrecognized configuration section userSettings - stop program reading user.config?

Question

In my c# form application (created in VS2010, using .NET 4.0) I use an application setting to store an output path.

Previously this setting was configured with a user scope, but I had to change its scope to application.

After doing this I now get an Unrecognized configuration section userSettings error on start up of the form (note the program has been executed before with the setting's scope set to user):

InnerException: System.Configuration.ConfigurationErrorsException
   Message=Unrecognized configuration section userSettings. (C:\Documents and Settings\Administrator\Local Settings\Application Data\CallCenterForm\CallCenterForm.vshost.exe_StrongName_bplf30wziudnpq0knzaacfuyomd5rv45\1.0.0.0\user.config line 3)
   Source=System.Configuration
   BareMessage=Unrecognized configuration section userSettings.
   Filename=C:\Documents and Settings\Administrator\Local Settings\Application Data\CallCenterForm\CallCenterForm.vshost.exe_StrongName_bplf30wziudnpq0knzaacfuyomd5rv45\1.0.0.0\user.config

So after doing some browsing this seems to be caused by the old user.config file still existing on the system, causing the program to read it and throw an error (I'm not sure what the actual underlying problem is). I can also confirm that when I remove the file the problem goes away.

Which brings me to my question, is there a way I can change the program so that it won't read the old user.config file, because deleting it manually isn't ideal as the program is already in production on multiple systems.

Apologies if this has been covered, but I couldn't find an answer.

In case it's helpful here's the contents of my App.config file:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
      <section name="CallCenterForm.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
    </sectionGroup>
  </configSections>
  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0"/>
  </startup>
  <applicationSettings>
    <CallCenterForm.Properties.Settings>
      <setting name="saved_output_dir" serializeAs="String">
        <value>c:\</value>
      </setting>
    </CallCenterForm.Properties.Settings>
  </applicationSettings>
</configuration>

Answer 1

I ran into this error myself today. The solution was to go into the Assembly Information dialogue of the project's properties and advance the assembly and file version info (ex. 1.0.0.0 to 1.0.1.0), save the changes, and rebuild the application. This will cause the compiler to reevaluate the configuration and cause the application to refrain from creating and reading a new user.config file corresponding to the new version due to there being no user settings in the new version.