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Changes to calendar items that are made on an iOS 8.3 device are not synchronized to Microsoft Outlook or Outlook Web App (OWA) mailboxes.

Note This issue does not apply to all time zones or regions. Known regions that are affected include Lebanon, Egypt, and parts of Brazil.

Additionally, the following exception is logged to the Exchange ActiveSync mailbox log for this device:

SyncCommand_ConvertRequestsAndApply_Add_Exception : 
Microsoft.Exchange.AirSync.SchemaConverter.Common.ConversionException: ExTimeZoneFromRegTimeZoneInfo failed: Specified argument was out of the range of valid values.
Parameter name: Hour
at Microsoft.Exchange.AirSync.SchemaConverter.Common.TimeZoneConverter.GetExTimeZone(Byte[] timeZoneInformation)
at Microsoft.Exchange.AirSync.SchemaConverter.XSO.XsoTimeZoneProperty.InternalCopyFromModified(IProperty srcProperty)
at Microsoft.Exchange.AirSync.SchemaConverter.XSO.XsoDataObject.CopyFrom(IProperty srcRootProperty)
at Microsoft.Exchange.AirSync.SyncCollection.ConvertClientToServerObjectAndSendIfNeeded(SyncCommandItem syncCommandItem, Boolean sendEnabled)
at Microsoft.Exchange.AirSync.SyncCollection.ConvertClientToServerObjectAndSave(SyncCommandItem syncCommandItem, UInt32& maxWindowSize, Boolean& mergeToClient)
at Microsoft.Exchange.AirSync.SyncCommand.ConvertRequestsAndApply(SyncCollection collection)


This issue occurs because the TimeZone value in the sync request is invalid.


This issue has been addressed in an iOS 8.4 update. For more information, see the following Apple Knowledge Base article:

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.

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