Error in saving config file

See more:

.NET2.0

C#

.NET

Hello!

I am trying to save MappedExe configuration file within user's AppData directory.
Problem occurs when I try to save encrypted connectionString.

This is the exception's message :

"System.Configuration.ConfigurationErrorsException: An error occured executing section handler for connectionStrings.-->System.Configuration.ConfigurationErrorsException: Failed to encrypt the section 'connectionStrings' using provider 'RsaProtectedConfigurationProvider'. Error message from provider: Object already exists.

It only occurs with common users within domain, I have no problems with admins, power users, work-groups etc.

This is part of code responsible for saving configuration data:

if (_configuration.ConnectionStrings.ConnectionStrings[Application.ProductName] == null)
{
    _configuration.ConnectionStrings.ConnectionStrings.Add(new ConnectionStringSettings(Application.ProductName, 
                                                                                        _connStringBuilder.ToString()));
}
else
{
    _configuration.ConnectionStrings.ConnectionStrings[Application.ProductName].ConnectionString = _connStringBuilder.ToString();
}
try
{
    if (!_configuration.ConnectionStrings.SectionInformation.IsProtected)
    {
        _configuration.ConnectionStrings.SectionInformation.ForceSave = true;
        _configuration.ConnectionStrings.SectionInformation.ProtectSection("RsaProtectedConfigurationProvider");
    }

    _configuration.Save(ConfigurationSaveMode.Minimal);
}
catch (Exception ex)
{
#if DEBUG
    MessageBox.Show(ex.ToString() + "\n" + ex.StackTrace);
#else
    throw;
#endif
}

Can you help me?

P.S. This is a ClickOnce solution.