Exchange calendar sync Expection

11:56:17 [email protected] [Exchange Web Services]  Синхронизация папки ‘[email protected]/Календарь/’
11:56:56 [email protected] [Exchange Web Services]  MailExceptions.ConnectionException: Элемент с тем же ключом уже был добавлен. —> System.ArgumentException: Элемент с тем же ключом уже был добавлен.
11:56:56    в System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
11:56:56    в System.Collections.Generic.Dictionary2.Insert(TKey key, TValue value, Boolean add) 11:56:56    в Microsoft.Exchange.WebServices.Data.TimeZoneDefinition.TryReadElementFromXml(EwsServiceXmlReader reader) 11:56:56    в Microsoft.Exchange.WebServices.Data.ComplexProperty.InternalLoadFromXml(EwsServiceXmlReader reader, XmlNamespace xmlNamespace, String xmlElementName, Func2 readAction)
11:56:56    в Microsoft.Exchange.WebServices.Data.ComplexProperty.LoadFromXml(EwsServiceXmlReader reader, XmlNamespace xmlNamespace, String xmlElementName)
11:56:56    в Microsoft.Exchange.WebServices.Data.ComplexProperty.LoadFromXml(EwsServiceXmlReader reader, String xmlElementName)
11:56:56    в Microsoft.Exchange.WebServices.Data.TimeZonePropertyDefinition.LoadPropertyValueFromXml(EwsServiceXmlReader reader, PropertyBag propertyBag)
11:56:56    в Microsoft.Exchange.WebServices.Data.PropertyBag.LoadFromXml(EwsServiceXmlReader reader, Boolean clear, PropertySet requestedPropertySet, Boolean onlySummaryPropertiesRequested)
11:56:56    в Microsoft.Exchange.WebServices.Data.EwsServiceXmlReader.ReadServiceObjectsCollectionFromXml[TServiceObject](XmlNamespace collectionXmlNamespace, String collectionXmlElementName, GetObjectInstanceDelegate1 getObjectInstanceDelegate, Boolean clearPropertyBag, PropertySet requestedPropertySet, Boolean summaryPropertiesOnly) 11:56:56    в Microsoft.Exchange.WebServices.Data.GetItemResponse.ReadElementsFromXml(EwsServiceXmlReader reader) 11:56:56    в Microsoft.Exchange.WebServices.Data.ServiceResponse.LoadFromXml(EwsServiceXmlReader reader, String xmlElementName) 11:56:56    в Microsoft.Exchange.WebServices.Data.MultiResponseServiceRequest1.ParseResponse(EwsServiceXmlReader reader)
11:56:56    в Microsoft.Exchange.WebServices.Data.ServiceRequestBase.ReadResponse(EwsServiceXmlReader ewsXmlReader)
11:56:56    в Microsoft.Exchange.WebServices.Data.SimpleServiceRequestBase.ReadResponseXml(Stream responseStream)
11:56:56    в Microsoft.Exchange.WebServices.Data.SimpleServiceRequestBase.ReadResponse(IEwsHttpWebResponse response)
11:56:56    в Microsoft.Exchange.WebServices.Data.MultiResponseServiceRequest1.Execute() 11:56:56    в Microsoft.Exchange.WebServices.Data.ExchangeService.InternalLoadPropertiesForItems(IEnumerable1 items, PropertySet propertySet, ServiceErrorHandling errorHandling)
11:56:56    в Microsoft.Exchange.WebServices.Data.ExchangeService.LoadPropertiesForItems(IEnumerable1 items, PropertySet propertySet) 11:56:56    в MailClient.Protocols.Exchange.ExchangeItemSynchronizer2.d__b.MoveNext()
11:56:56 в System.Linq.Enumerable.d__313.MoveNext()<br alt="" name="" rel="" target="" title="" type="" value="">11:56:56 в System.Collections.Generic.List1…ctor(IEnumerable1 collection)<br alt="" name="" rel="" target="" title="" type="" value="">11:56:56 в System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
11:56:56 в System.Linq.Enumerable.ToArray[TSource](IEnumerable1 source)<br alt="" name="" rel="" target="" title="" type="" value="">11:56:56 в MailClient.Protocols.Common.ScheduleItemSynchronizeContext1.StoreItems(SynchronizationType type, IEnumerable1 newItems)<br alt="" name="" rel="" target="" title="" type="" value="">11:56:56 в MailClient.Protocols.Common.ItemSynchronizeContext2.Synchronize[T](SynchronizationType synchronizationType, IEnumerable1 items, Func2 getUniqueId, Func3 hasChanged, Func2 isDeleted, Func2 convertItems, Action2 updateItem)
11:56:56 в MailClient.Protocols.Exchange.ExchangeItemSynchronizer2.Synchronize(IItemSynchronizeContext1 synchronizeContext, Folder folder, CancellationToken cancellationToken)
11:56:56 в MailClient.Protocols.Common.ItemSynchronizer`2.<>c DisplayClass2e.<>c DisplayClass33.b__2a(WorkerStatus status, CancellationToken cancellationToken)
11:56:56 в MailClient.Protocols.Exchange.ExchangeGenericCommand.Execute(WorkerStatus status)
11:56:56 — Конец трассировки внутреннего стека исключений —


Any ideas why this is happening? Need help :frowning: