Hello to everyone facing this problem! I too faced it!

FIRST: do not under ANY CIRCUMSTANCES download the dll directly from a non-official source. This includes places like dllfiles.com -- dlls are pieces of executable code that can do low level system actions. You have no idea if those files have been changed, if they contain viruses, or if they will generally cause problems.

So what can you do?

For the long version, the solution is here: http://pcsupport.about.com/od/findby..._39dll-dll.htm

Here's a quick summary. Do these steps in order:

1) Make sure Windows is fully updated. Every time you restart you have to manually "check for updates" to make sure there aren't any missing.
2) Make sure your graphics card drivers are fully updated. Google is your friend here.
3) Make sure your directx is fully updated. Follow the links from the article above to do this. They point you directly to Microsoft. Be very careful not to just download random files from the internet
4) Reinstall League of Legends.

After each of those steps you need to restart your computer and try launching again. Any of them COULD solve your problem, but if you are like me, none of those steps will work.

5) Restore the specific dll directly from the DirectX Package and then restart -- instructions: http://pcsupport.about.com/od/fixthe...toredx9dll.htm

#5 is what solved the problem for me. For whatever reason, even though I had used that exact same package to update DirectX, I had to replace the file in C:\Windows\System32 directly.

I hope this helps another summoner get in the game!

If anyone is still having this issue, please attach your DxDiag report.

------------------
System Information
------------------
Time of this report: 10/24/2012, 06:04:30
Machine name: KAMIKAZECOPILOT
Operating System: Debug Windows 8 Pro 32-bit (6.2, Build 9200) (9200.win8_rtm.120725-1247)
Language: English (Regional Setting: English)
System Manufacturer: TOSHIBA
System Model: Satellite X205
BIOS: Ver 1.00PARTTBL
Processor: Intel(R) Core(TM)2 Duo CPU T5550 @ 1.83GHz (2 CPUs), ~1.8GHz
Memory: 2048MB RAM
Available OS Memory: 2046MB RAM
Page File: 1102MB used, 2992MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.02.9200.16384 32bit Unicode

------------
DxDiag Notes
------------
Display Tab 1: No problems found.
Sound Tab 1: No problems found.
Sound Tab 2: No problems found.
Sound Tab 3: No problems found.
Input Tab: No problems found.

--------------------
DirectX Debug Levels
--------------------
Direct3D: 0/4 (retail)
DirectDraw: 0/4 (debug)
DirectInput: 0/5 (retail)
DirectMusic: 0/5 (retail)
DirectPlay: 0/9 (retail)
DirectSound: 0/5 (debug)
DirectShow: 0/6 (debug)

---------------
Display Devices
---------------
Card name: NVIDIA GeForce 8700M GT (Microsoft Corporation - WDDM v1.2)
Manufacturer: NVIDIA
Chip type: GeForce 8700M GT
DAC type: Integrated RAMDAC
Device Type: Full Device
Device Key: Enum\PCI\VEN_10DE&DEV_0409&SUBSYS_FF001179&REV_A1
Display Memory: 1266 MB
Dedicated Memory: 499 MB
Shared Memory: 767 MB
Current Mode: 1440 x 900 (32 bit) (60Hz)
Monitor Name: Generic PnP Monitor
Monitor Model: unknown
Monitor Id: LPLA002
Native Mode: 1440 x 900(p) (59.901Hz)
Output Type: Internal
Driver Name: nvd3dum.dll,nvwgf2um.dll,nvwgf2um.dll
Driver File Version: 9.18.0013.0286 (English)
Driver Version: 9.18.13.286
DDI Version: 10
Feature Levels: 10.0,9.3,9.2,9.1
Driver Model: WDDM 1.2
Graphics Preemption: DMA
Compute Preemption: DMA
Driver Attributes: Final Retail
Driver Date/Size: 6/27/2012 19:06:14, 15385960 bytes
WHQL Logo'd: Yes
WHQL Date Stamp:
Device Identifier: {D7B71E3E-4749-11CF-D773-0DDF1CC2C435}
Vendor ID: 0x10DE
Device ID: 0x0409
SubSys ID: 0xFF001179
Revision ID: 0x00A1
Driver Strong Name: nv_LH.inf:23f60d05dba85e3e:Section031:9.18.13.286: pci\ven_10de&dev_0409&subsys_ff001179
Rank Of Driver: 00E30001
Video Accel: ModeMPEG2_A ModeMPEG2_C ModeVC1_C ModeWMV9_C
DXVA2 Modes: DXVA2_ModeMPEG2_IDCT DXVA2_ModeVC1_IDCT DXVA2_ModeWMV9_IDCT DXVA2_ModeH264_VLD_NoFGT
Deinterlace Caps: {6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(YUY2,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(YUY2,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(YUY2,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(YUY2,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(UYVY,UYVY) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(UYVY,UYVY) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(UYVY,UYVY) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(UYVY,UYVY) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(YV12,0x32315659) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(YV12,0x32315659) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(YV12,0x32315659) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(YV12,0x32315659) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(NV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(NV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(NV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(NV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(IMC1,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(IMC1,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(IMC1,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(IMC1,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(IMC2,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(IMC2,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(IMC2,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(IMC2,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(IMC3,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(IMC3,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(IMC3,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(IMC3,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(IMC4,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(IMC4,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(IMC4,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(IMC4,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(S340,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(S340,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(S340,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(S340,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(S342,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{F9F19DA5-3B09-4B2F-9D89-C64753E3EAAB}: Format(In/Out)=(S342,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{5A54A0C9-C7EC-4BD9-8EDE-F3C75DC4393B}: Format(In/Out)=(S342,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(S342,UNKNOWN) Frames(Prev/Fwd/Back)=(0,0,0) Caps=
D3D9 Overlay: Supported
DXVA-HD: Supported
DDraw Status: Enabled
D3D Status: Enabled
AGP Status: Enabled

http://www.microsoft.com/en-us/downl...ion.aspx?id=35

Try that and doesn't matter if you already have newest directx, this file worked for two of my computers, so should work for most of us. Good Luck.

Thank time, that actually worked, looks like windows update doesn't cover that.

Thank you so much!!! <3

Worked like a charm

If the url changes in future, you want to download the "DirectX End-User Runtime Web Installer" from microsoft.