Here's the exception stack:

DotNetNuke.Services.Exceptions.ModuleLoadException: Cannot insert explicit value for identity column in table 'DNN_Events' when IDENTITY_INSERT is set to OFF. Violation of PRIMARY KEY constraint 'PK_DNN_EventsCategory'. Cannot insert duplicate key in object 'DNN_EventsCategory'. Violation of PRIMARY KEY constraint 'PK_DNN_EventsLocation'. Cannot insert duplicate key in object 'DNN_EventsLocation'. The statement has been terminated. The statement has been terminated. ---> System.Data.SqlClient.SqlException: Cannot insert explicit value for identity column in table 'DNN_Events' when IDENTITY_INSERT is set to OFF. Violation of PRIMARY KEY constraint 'PK_DNN_EventsCategory'. Cannot insert duplicate key in object 'DNN_EventsCategory'. Violation of PRIMARY KEY constraint 'PK_DNN_EventsLocation'. Cannot insert duplicate key in object 'DNN_EventsLocation'. The statement has been terminated. The statement has been terminated. at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteNonQuery(SqlConnection connection, CommandType commandType, String commandText, SqlParameter[] commandParameters) at Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteNonQuery(String connectionString, CommandType commandType, String commandText, SqlParameter[] commandParameters) at Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteNonQuery(String connectionString, String spName, Object[] parameterValues) at DotNetNuke.Modules.Events.Data.SqlDataProvider.EventsAVCalendarImport(Int32 CalendarModuleID, Int32 EventModuleID, String Version, Int32 TimeZoneOffset, Int32 PortalID, Boolean ImportCategory, Boolean ImportLocation) at DotNetNuke.Modules.Events.EventController.EventsAVCalendarImport(Int32 CalendarModuleID, Int32 EventModuleID, String Version, Int32 TimeZoneOffset, Int32 PortalID, Boolean ImportCategory, Boolean ImportLocation) at DotNetNuke.Modules.Events.ImportAVCalendar.cmdImport_Click(Object sender, EventArgs e) --- End of inner exception stack trace ---

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