Calendar sync exchange issue

I’ve got eM Client for MS Exchange mail server. It works fine. But there is no calendar sync. There are no events though I have them with MS Outlook.

My logs

12:05:56 mail@mailserver.com [Exchange Web Services]  Синхронизация папки ‘mail@mailserver.com/Календарь/’
12:06:02 mail@mailserver.com [Exchange Web Services]  MailExceptions.ConnectionException: An item with the same key has already been added. —> System.ArgumentException: An item with the same key has already been added.
12:06:02    at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
12:06:02    at System.Collections.Generic.Dictionary2.Insert(TKey key, TValue value, Boolean add) 12:06:02    at Microsoft.Exchange.WebServices.Data.TimeZoneDefinition.TryReadElementFromXml(EwsServiceXmlReader reader) 12:06:02    at Microsoft.Exchange.WebServices.Data.ComplexProperty.InternalLoadFromXml(EwsServiceXmlReader reader, XmlNamespace xmlNamespace, String xmlElementName, Func2 readAction)
12:06:02    at Microsoft.Exchange.WebServices.Data.ComplexProperty.LoadFromXml(EwsServiceXmlReader reader, XmlNamespace xmlNamespace, String xmlElementName)
12:06:02    at Microsoft.Exchange.WebServices.Data.ComplexProperty.LoadFromXml(EwsServiceXmlReader reader, String xmlElementName)
12:06:02    at Microsoft.Exchange.WebServices.Data.TimeZonePropertyDefinition.LoadPropertyValueFromXml(EwsServiceXmlReader reader, PropertyBag propertyBag)
12:06:02    at Microsoft.Exchange.WebServices.Data.PropertyBag.LoadFromXml(EwsServiceXmlReader reader, Boolean clear, PropertySet requestedPropertySet, Boolean onlySummaryPropertiesRequested)
12:06:02    at Microsoft.Exchange.WebServices.Data.EwsServiceXmlReader.ReadServiceObjectsCollectionFromXml[TServiceObject](XmlNamespace collectionXmlNamespace, String collectionXmlElementName, GetObjectInstanceDelegate1 getObjectInstanceDelegate, Boolean clearPropertyBag, PropertySet requestedPropertySet, Boolean summaryPropertiesOnly) 12:06:02    at Microsoft.Exchange.WebServices.Data.GetItemResponse.ReadElementsFromXml(EwsServiceXmlReader reader) 12:06:02    at Microsoft.Exchange.WebServices.Data.ServiceResponse.LoadFromXml(EwsServiceXmlReader reader, String xmlElementName) 12:06:02    at Microsoft.Exchange.WebServices.Data.MultiResponseServiceRequest1.ParseResponse(EwsServiceXmlReader reader)
12:06:02    at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.ReadResponse(EwsServiceXmlReader ewsXmlReader)
12:06:02    at Microsoft.Exchange.WebServices.Data.SimpleServiceRequestBase.ReadResponseXml(Stream responseStream)
12:06:02    at Microsoft.Exchange.WebServices.Data.SimpleServiceRequestBase.ReadResponse(IEwsHttpWebResponse response)
12:06:02    at Microsoft.Exchange.WebServices.Data.MultiResponseServiceRequest1.Execute() 12:06:02    at Microsoft.Exchange.WebServices.Data.ExchangeService.InternalLoadPropertiesForItems(IEnumerable1 items, PropertySet propertySet, ServiceErrorHandling errorHandling)
12:06:02    at Microsoft.Exchange.WebServices.Data.ExchangeService.LoadPropertiesForItems(IEnumerable1 items, PropertySet propertySet) 12:06:02    at MailClient.Protocols.Exchange.ExchangeItemSynchronizer2.d__b.MoveNext()
12:06:02 at System.Linq.Enumerable.d__313.MoveNext()<br>12:06:02 at System.Collections.Generic.List1…ctor(IEnumerable1 collection)<br>12:06:02 at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
12:06:02 at System.Linq.Enumerable.ToArray[TSource](IEnumerable1 source)<br>12:06:02 at MailClient.Protocols.Common.ScheduleItemSynchronizeContext1.StoreItems(SynchronizationType type, IEnumerable1 newItems)<br>12:06:02 at MailClient.Protocols.Common.ItemSynchronizeContext2.Synchronize[T](SynchronizationType synchronizationType, IEnumerable1 items, Func2 getUniqueId, Func3 hasChanged, Func2 isDeleted, Func2 convertItems, Action2 updateItem)
12:06:02 at MailClient.Protocols.Exchange.ExchangeItemSynchronizer2.Synchronize(IItemSynchronizeContext1 synchronizeContext, Folder folder, CancellationToken cancellationToken)
12:06:02 at MailClient.Protocols.Common.ItemSynchronizer`2.<>c DisplayClass2e.<>c DisplayClass33.b__2a(WorkerStatus status, CancellationToken cancellationToken)
12:06:02 at MailClient.Protocols.Exchange.ExchangeGenericCommand.Execute(WorkerStatus status)
12:06:02 — End of inner exception stack trace —
12:06:02 at MailClient.Protocols.Exchange.ExchangeGenericCommand.Execute(WorkerStatus status)
12:06:02 at MailClient.Commands.Command.Process(WorkerStatus status)

Hello Александр,
could you please tell me what version of eM Client are you currently running? Check the Help>About section for the exact version number.

Regards,
Olivia

Hello Olivia,
My current eM Client version is 6.0.24928.0

Hello Александр,
we’ll need more detailed logs to determine what exactly is wrong.
Please go to Tools>Settings>Advanced and turn on Exchange Web Services logs for your account.
Restart eM Client.
When the calendar sync error happens again, go back to Advanced settings and press Send logs.
Change the recipient of the message to rust@emclient.com and add a link to this forum topic to the body of the email.

Regards,
Olivia

Hello!
I have some problem.
Do you have solution?

Hello Evgeny,
what version of eM Client are you running? Check Help>About section.
What mail account does this happen with?

Regards,
Olivia

Version 7.0.27943.0
standard corporate account

Hello Evgeny,
Please go to Tools>Settings>Advanced and turn on Exchange Web Services logs for your account.
Restart eM Client.
When the calendar sync error happens again, go back to Advanced settings and press Send logs.
Change the recipient of the message to rust@emclient.com and add a link to this forum topic to the body of the email.

Regards,
Olivia

did it

any news?

Hey Evgeny & Olivia!
I’ve got the same issue. After sending logs noone updated me about this issue and I’ve moved back to MS (though eM is really great).
Let me guess that the problem is about MS Exchange server negotiation with Cyrillic based email clients (in both cases it is Russian - am I correct?). Probably It is calendar culture specific features that crashes synchronization. Olivia does it make sense? Have you tested eM for integration in such environment? 

Hello!
I think this is not only cyrillic problem.

Yeah… Obviously it shouldn’t. But smth crashes eM. What if the problem is about calendar folder name (invisible or Russian letters)? MS exchange uses culture specific folder names: ‘mail@mailserver.com/Календарь’ (not ‘mail@mailserver.com/Calendar’). Parsing this name generates error “An item with the same key has already been added.”

Yes, you absolutely right! I mean, this is global problem with non-english MS Exchange

Is there a solution for this? It seems like I have the same problem on a danish exchange server, and I cannot sync my calendar.
I am still on my Trial, and this problem is essential if our company should invest in Pro versions.