--- title: Release Notes - .NET FIX Engine - Version 3.20.0.0 description: Release Notes - .NET FIX Engine - Version 3.20.0.0 --- [OnixS ](https://www.onixs.biz/) - [Products](https://www.onixs.biz/products.html) - [Support](https://www.onixs.biz/support.html) - [Contact us](https://www.onixs.biz/contact-us) Search Menu # Release Notes - .NET FIX Engine - Version 3.20.0.0 - [Home](https://www.onixs.biz) - [Release Notes](https://www.onixs.biz/release-notes/) 4 Nov 2015 ## Improvement - [[DOTNET-1793](http://support.onixs.biz/browse/DOTNET-1793)] - BREAKING CHANGE: Threading.ThreadPriority enum should be used in Session.*ThreadPriority - [[DOTNET-1774](http://support.onixs.biz/browse/DOTNET-1774)] - Information about EngineSettings.LocalTimeUsage property should be added to Programming Guide - [[DOTNET-1751](http://support.onixs.biz/browse/DOTNET-1751)] - Information about the logging order of incoming messages should be added to Programming Guide - [[DOTNET-1738](http://support.onixs.biz/browse/DOTNET-1738)] - 'How to control the order of the tags' question should be added to FAQ section - [[DOTNET-1710](http://support.onixs.biz/browse/DOTNET-1710)] - Add description of how to modify outgoing message in outgoing callback to documentation - [[DOTNET-1705](http://support.onixs.biz/browse/DOTNET-1705)] - Describe settings which allow user create a maximum number of sessions - [[DOTNET-1700](http://support.onixs.biz/browse/DOTNET-1700)] - Add more details about Custom FIXML dictionaries - [[DOTNET-1696](http://support.onixs.biz/browse/DOTNET-1696)] - Ability to process the custom main XML schema file which contains all definitions itself - [[DOTNET-1681](http://support.onixs.biz/browse/DOTNET-1681)] - Message.Validate() method should validate required fields for the application level only - [[DOTNET-1674](http://support.onixs.biz/browse/DOTNET-1674)] - Thread Safety section should be added to Programming Guide - [[DOTNET-1653](http://support.onixs.biz/browse/DOTNET-1653)] - ErrorEvent should be invoked if there is an unhandled exception in InboundApplicationMsgEvent handler - [[DOTNET-1629](http://support.onixs.biz/browse/DOTNET-1629)] - Add default values of classes properties to Programming Guide - [[DOTNET-1613](http://support.onixs.biz/browse/DOTNET-1613)] - SendingBytes.ToFixString method should not throw exceptions ## New Feature - [[DOTNET-1790](http://support.onixs.biz/browse/DOTNET-1790)] - Session.TcpNoDelayOption - [[DOTNET-1787](http://support.onixs.biz/browse/DOTNET-1787)] - Group.Set(int, int, ArraySegment) - [[DOTNET-1784](http://support.onixs.biz/browse/DOTNET-1784)] - EngineSettings.LogOutboundMessages - [[DOTNET-1783](http://support.onixs.biz/browse/DOTNET-1783)] - EngineSettings.LogInboundMessages - [[DOTNET-1781](http://support.onixs.biz/browse/DOTNET-1781)] - Group.TryGetDecimal(..) - [[DOTNET-1780](http://support.onixs.biz/browse/DOTNET-1780)] - Group.TryGetByteArray(..) - [[DOTNET-1767](http://support.onixs.biz/browse/DOTNET-1767)] - EngineSettings.LogFileName property - [[DOTNET-1766](http://support.onixs.biz/browse/DOTNET-1766)] - EngineSettings.MessageGrouping property - [[DOTNET-1765](http://support.onixs.biz/browse/DOTNET-1765)] - Session.ReceiveSpinningTimeoutUsec property - [[DOTNET-1764](http://support.onixs.biz/browse/DOTNET-1764)] - EngineSettings.ReceiveSpinningTimeout property - [[DOTNET-1763](http://support.onixs.biz/browse/DOTNET-1763)] - Update the ICE Trading Client sample in accordance with ICE FIX OS Reference Manual - 3.4.9 - [[DOTNET-1717](http://support.onixs.biz/browse/DOTNET-1717)] - Add setter/getter to the Group class for DateTime values - [[DOTNET-1715](http://support.onixs.biz/browse/DOTNET-1715)] - Add info that AnyCpu paltform is not supported to FAQ - [[DOTNET-1697](http://support.onixs.biz/browse/DOTNET-1697)] - FixmlConverter(ProtocolVersion version, String schemaString) constructor - [[DOTNET-1694](http://support.onixs.biz/browse/DOTNET-1694)] - FixmlConverter.AddCustomMessage(..) - [[DOTNET-1692](http://support.onixs.biz/browse/DOTNET-1692)] - FixmlConverter.AddCustomRepeatingGroup(..) - [[DOTNET-1691](http://support.onixs.biz/browse/DOTNET-1691)] - ErrorEventArgs.IncomingMessageBytes property - [[DOTNET-1688](http://support.onixs.biz/browse/DOTNET-1688)] - Session.WarmUp(SerializedMessage) - [[DOTNET-1683](http://support.onixs.biz/browse/DOTNET-1683)] - Message.Validate(MessageValidationFlags validationFlags) - [[DOTNET-1678](http://support.onixs.biz/browse/DOTNET-1678)] - Session.IncomingMessageGapQueueMaximumSize - [[DOTNET-1668](http://support.onixs.biz/browse/DOTNET-1668)] - ConfirmationLogonMessageErrorException - [[DOTNET-1667](http://support.onixs.biz/browse/DOTNET-1667)] - TimeoutException - [[DOTNET-1666](http://support.onixs.biz/browse/DOTNET-1666)] - UnexpectedSequenceNumberException - [[DOTNET-1665](http://support.onixs.biz/browse/DOTNET-1665)] - LinkErrorException - [[DOTNET-1663](http://support.onixs.biz/browse/DOTNET-1663)] - Session.IgnoreLessThanExpectedSequenceNumber property - [[DOTNET-1660](http://support.onixs.biz/browse/DOTNET-1660)] - Add setter/getter to the Group class for char values - [[DOTNET-1628](http://support.onixs.biz/browse/DOTNET-1628)] - FieldSet.Set(int, ArraySegment) - [[DOTNET-1603](http://support.onixs.biz/browse/DOTNET-1603)] - Session.PreFill methods for a single message ## Bug - [[DOTNET-1739](http://support.onixs.biz/browse/DOTNET-1739)] - BREAKING CHANGE: Errors in standard FIX dictionaries - [[DOTNET-1734](http://support.onixs.biz/browse/DOTNET-1734)] - Data types of fields are incorrectly parsed from FIXML scheme for versions 5.0SP1/5.0SP2 ### Related articles [See all release notes](https://www.onixs.biz/release-notes/) 11 Nov 2024 ##### [ Release Notes - .NET Framework FIX Engine - Version 4.12.0.0 ](https://www.onixs.biz/release-notes/release-notes-net-framework-fix-engine-version-4-12-0-0.html) 30 May 2024 ##### [ Release Notes - .NET Framework FIX Engine - Version 4.11.0.0 ](https://www.onixs.biz/release-notes/release-notes-net-framework-fix-engine-version-4-11-0-0.html) 23 Jan 2024 ##### [ Release Notes - .NET Framework FIX Engine - Version 4.10.1.0 ](https://www.onixs.biz/release-notes/release-notes-net-framework-fix-engine-version-4-10-1-0.html) 28 Dec 2023 ##### [ Release Notes - 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