protected void Page_Load(object sender, EventArgs e) {
Configuration config;
ConfigurationSection configSection;
config = WebConfigurationManager.OpenWebConfiguration
(Request.ApplicationPath);
configSection = config.GetSection("connectionStrings");
if (configSection != null) {
if (!(configSection.SectionInformation.IsLocked)) {
configSection.SectionInformation.ProtectSection("
DataProtectionConfigurationProvider");
config.Save();
} } }


To unprotect :

Public Sub Page_Load()
Dim config As Configuration
Dim configSection As ConfigurationSection
config = WebConfigurationManager.OpenWebConfiguration
(Request.ApplicationPath)
configSection = config.GetSection("connectionStrings")
If Not (configSection Is Nothing) Then
If Not (configSection.SectionInformation.IsLocked) Then
configSection.SectionInformation.UnprotectSection()
config.Save()
End If
End If
End Sub