An item with the same key has already been added.
I'm suddenly getting the 'An item with the same key has already been added.' error when running from Visual Studio (2015 - Ver 14.0.25431.01). I hit this error before the site comes up. The same code has no problem when running in IIS. Any advice appreciated!
[ArgumentException: An item with the same key has already been added.] System.ThrowHelper.ThrowArgumentException(ExceptionResource resource) +52 System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add) +12988770 Telerik.Sitefinity.Configuration.ConfigElementDictionary`2.Add(TKey key, TElement element) +150 Telerik.Sitefinity.Configuration.ConfigElementDictionary`2.Add(TElement element) +30 Telerik.Sitefinity.Security.Configuration.SecurityConfig.LoadDefaults() +1497 Telerik.Sitefinity.Security.Configuration.SecurityConfig.OnPropertiesInitialized() +78 Telerik.Sitefinity.Configuration.ConfigSection.InitializeProperties() +18 Telerik.Sitefinity.Configuration.ConfigElement.EnsurePropertiesInitialized() +106 Telerik.Sitefinity.Configuration.ConfigElement.get_Properties() +15 Telerik.Sitefinity.Configuration.Data.XmlConfigProvider.LoadAttributes(ConfigElement element, XmlReader reader, ConfigPolicyHandler policyHandler, String policyName, UpgradingInfo upgradingInfo, Boolean isNew) +137 Telerik.Sitefinity.Configuration.Data.XmlConfigProvider.LoadElement(ConfigElement element, XmlReader reader, ConfigPolicyHandler policyHandler, String policyName, UpgradingInfo upgradingInfo, Boolean isNew, Boolean validateTagName) +160 Telerik.Sitefinity.Configuration.Data.XmlConfigProvider.LoadSectionFromReader(ConfigSection section, XmlReader reader, ConfigPolicyHandler policyHandler, String policyName, Boolean checkForUpgrade, UpgradingInfo& upgradingInfo) +290 Telerik.Sitefinity.Configuration.Data.XmlConfigProvider.LoadSectionFromFile(ConfigSection section, ConfigPolicyHandler policyHandler, String policyName, Boolean withUpgrade) +93 Telerik.Sitefinity.Configuration.Data.XmlConfigProvider.LoadSection(ConfigSection section, ConfigPolicyHandler policyHandler, String policyName) +41 Telerik.Sitefinity.Configuration.ConfigSection.Initialize(ConfigProvider provider, ConfigPolicyHandler policyHandler, String policyName, Boolean singlePolicy) +227 Telerik.Sitefinity.Configuration.ConfigSection.Initialize(ConfigProvider provider) +16 Telerik.Sitefinity.Configuration.Config.GetSectionInternal(Type sectionType, Boolean safeMode, String sectionName) +147 Telerik.Sitefinity.Configuration.Config.GetSectionPrivate(Type sectionType, Boolean safeMode, String sectionName) +135 Telerik.Sitefinity.Configuration.Config.GetSectionPrivate(Boolean safeMode) +99 Telerik.Sitefinity.Configuration.Config.Get(Boolean safeMode) +46 Telerik.Sitefinity.Configuration.Config.Get() +36 Telerik.Sitefinity.Security.SecurityManager..cctor() +292
I'm getting the same exact error message all of a sudden. I'm also running VS 2015. Have you figured out a fix?
Have you had any luck with this? I'm having the exact same issue.
I have not yet applied this patch, but I believe this may be the solution. Even though the link implies the issue is with Windows 10 update, it' actually with .Net 4.7