I'm on Windows and getting the same previously mentioned error. Here's the full errdump I'm getting after allowing CKAN to update on its own. The only version of CKAN I had installed previously was the last major release. I did run the full CKAN uninstall procedure in addition to removing the CKAN folder in C:/Users/username/local and there's no change.
Unhandled Exception: System.ArgumentException: Object of type 'System.Globalization.CalendarId[]' cannot be converted to type 'System.Int32[]'.
at System.RuntimeType.TryChangeType(Object value, Binder binder, CultureInfo culture, Boolean needsSpecialCast)
at System.RuntimeType.CheckValue(Object value, Binder binder, CultureInfo culture, BindingFlags invokeAttr)
at System.Reflection.RtFieldInfo.UnsafeSetValue(Object obj, Object value, BindingFlags invokeAttr, Binder binder, CultureInfo culture)
at System.Runtime.Serialization.FormatterServices.SerializationSetValue(MemberInfo fi, Object target, Object value)
at System.Runtime.Serialization.ObjectManager.CompleteObject(ObjectHolder holder, Boolean bObjectFullyComplete)
at System.Runtime.Serialization.ObjectManager.DoNewlyRegisteredObjectFixups(ObjectHolder holder)
at System.Runtime.Serialization.ObjectManager.RegisterObject(Object obj, Int64 objectID, SerializationInfo info, Int64 idOfContainingObj, MemberInfo member, Int32[] arrayIndex)
at System.Runtime.Serialization.Formatters.Binary.ObjectReader.RegisterObject(Object obj, ParseRecord pr, ParseRecord objectPr, Boolean bIsString)
at System.Runtime.Serialization.Formatters.Binary.ObjectReader.ParseObjectEnd(ParseRecord pr)
at System.Runtime.Serialization.Formatters.Binary.ObjectReader.Parse(ParseRecord pr)
at System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run()
at System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage)
at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage)
at System.Resources.ResourceReader.DeserializeObject(Int32 typeIndex)
at System.Resources.ResourceReader._LoadObjectV2(Int32 pos, ResourceTypeCode& typeCode)
at System.Resources.ResourceReader.LoadObjectV2(Int32 pos, ResourceTypeCode& typeCode)
at System.Resources.ResourceReader.LoadObject(Int32 pos)
at System.Resources.ResourceReader.ResourceEnumerator.get_Entry()
at System.Resources.ResourceReader.ResourceEnumerator.get_Current()
at System.ComponentModel.ComponentResourceManager.FillResources(CultureInfo culture, ResourceSet& resourceSet)
at System.ComponentModel.ComponentResourceManager.FillResources(CultureInfo culture, ResourceSet& resourceSet)
at System.ComponentModel.ComponentResourceManager.FillResources(CultureInfo culture, ResourceSet& resourceSet)
at System.ComponentModel.ComponentResourceManager.ApplyResources(Object value, String objectName, CultureInfo culture)
at System.ComponentModel.ComponentResourceManager.ApplyResources(Object value, String objectName)
at CKAN.Main.InitializeComponent()
at CKAN.Main..ctor(String[] cmdlineArgs, KSPManager mgr, Boolean showConsole)
at CKAN.GUI.Main_(String[] args, KSPManager manager, Boolean showConsole)
at CKAN.CmdLine.MainClass.RunSimpleAction(Options cmdline, CommonOptions options, String[] args, IUser user, KSPManager manager)
at CKAN.CmdLine.MainClass.Execute(KSPManager manager, CommonOptions opts, String[] args)
at CKAN.CmdLine.MainClass.Main(String[] args)