Read Me

This Readme file contains detailed information and troubleshooting tips for the Unreal Development Kit (UDK). You can find more information at

UDK includes upgrades made to Unreal Engine 3 following the release of Unreal Tournament 3.

This version of UDK is early. The runtime is an active work in progress that will have frequent updates and releases.

A. System Requirements

UDK requires a personal computer with the following system configuration:


  • Windows XP SP2 or Windows Vista
  • 2.0+ GHz processor
  • 2 GB system RAM
  • SM3-compatible video card
  • 3 GB free hard drive space

Recommended for Content Development:

  • Windows Vista 64 SP2
  • 2.0+ GHz multi-core processor
  • 8 GB system RAM
  • NVIDIA 8000 series or higher graphics card
  • Plenty of HDD space

The UDK will install .NET Framework 3.5 Service Pack 1 if you don't already have it. This will require an internet connection.

B. Installation

Run the UDK installer (UDKInstall.exe)

This will install UDK to a new folder based on the release date of this version. This is to make sure this version doesn't use any old Epic-provided content. However, you should be able to open old user-created content in the new version of the editor. The UDK editor can then be run from the Programs menu.

C. Using the Editor

Note: Respect the rights of others. By making custom content available, you acknowledge that you are solely responsible for that content. You agree that you have all necessary rights to make any content publicly available and that it complies with all applicable laws and does not violate the rights of any person or entity.

For more information on working with this game editor, see

For information on setting up Swarm see

D. Getting Help

Epic Games, Inc. will not be providing direct support for this product. There is, however, a wealth of information about UDK available on the Unreal Developer Network:

Community forums are also available:

E. Known Configuration Issues

Visit the official Web site for the latest updates and support information:

Certain keys on non-English keyboards do not function correctly: On some non-English keyboards, certain keys do not work as expected. In other words, what appears when you press the key is not what is printed on the key. To fix this problem, remap any problem keys.

F. Known Graphics Issues

Video Settings: The default game settings chosen for the UDK are very aggressive, prioritizing visual acuity over performance. You should experiment with your video settings to find the best balance for your PC and for games that you create.

You can override these settings in the [SystemSettings] section of UTGame\Config\UTEngine.ini:

Game authors can prepare their game to automatically scale these settings based on machine performance by preparing their DefaultCompat.ini as explained here:

The "setres" command can also be used to lower your resolution to provide better performance as well SETRES [height]x[width][w|f] - changes the resolution (w = windowed; f = fullscreen) (For example: setres 800x600f) When using the game editor, windows can get rendered behind viewports: To fix this problem, do not use the game editor with a floating taskbar.

1. Graphics Card Drivers and Manufacturers

Be sure that you have installed the latest driver for your graphics card. Many video issues will be resolved simply by updating your graphics card's drivers. UDK may not properly detect some older graphics cards because their video drivers are not DirectX 9.0c compliant. Contact your graphics card manufacturer for updated drivers, or install the latest reference drivers for your graphics card chipset. Note that many reference drivers are not supported by the chipset manufacturer.

2. Graphics Card Manufacturers' Web Sites

Graphics Card Manufacturers’ Web Sites:

G. Known Hardware Issues

1 - NVIDIA cards with on-board SLI have issues displaying certain property windows with multi-gpu mode turned off.

H. General Audio Issues


If you do experience audio crashes, try running without sound by appending "-nosound"; to the UDK editor shortcut.

Copyright © 1998-2014. Epic Games, Inc. All rights reserved. ActorLineCheck, An Efficient Parametric Algorithm for Octree Traversal by J.Revelles/C.Ureña/M.Lastra (University of Granada, Spain). Uses Bink Video, Copyright © 1997-2009 by RAD Game Tools, Inc. Convex Decomposition Library: Copyright © 2007 by John W. Ratcliff. libresample: Copyright © 2006 Feeling Software. libXML2: Copyright © 1998-2003 Daniel Veillard. All Rights Reserved. Mersenne Prime Twister (SSE version): Copyright © 2006, 2007 Mutsuo Saito, Makoto Matsumoto and Hiroshima University. All rights reserved. This product includes code licensed from NVIDIA. PhysX SDK, Copyright © 2006 NVIDIA Corporation. All rights reserved. Ogg Vorbis Audio Compression, Copyright © 2009, Xiph.Org Foundation. Vorbis Quality Improvements, Copyright © 2003-2008 Aoyumi Vorbis SSE Optimisations, Copyright © 1994-2006. Zlib, Copyright © 1995-2004 Jean-loup Gailly and Mark Adler.

This computer program, the characters, artwork, trademarks and all other conceivable intellectual property rights related to this software are protected by copyright laws and international treaties. This product was produced through the efforts of many people who earn their livelihood from its lawful use under license. The unauthorized use, copying, or distribution of this game or any portion will be prosecuted and may result in civil or criminal penalties.