Voila après avoir retéléchargé minecraft le je met's un message d'erreur:

---- Minecraft Crash Report ----
// Oh - I know what I did wrong!

Time: 26/10/14 15:18
Description: Initializing game

org.lwjgl.LWJGLException: Pixel format not accelerated
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelForma
t(Native
Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat
(WindowsPeerInfo.java:52)

at org.lwjgl.opengl.WindowsDisplay.createWindow(Windo
wsDisplay.java:252)

at org.lwjgl.opengl.Display.createWindow(Display.java
:306)

at org.lwjgl.opengl.Display.create(Display.java:848)

at org.lwjgl.opengl.Display.create(Display.java:757)

at org.lwjgl.opengl.Display.create(Display.java:739)

at bsu.am(SourceFile:523)
at bsu.aj(SourceFile:352)
at bsu.a(SourceFile:299)
at net.minecraft.client.main.Main.main(SourceFile:120
)

A detailed walkthrough of the error, its code path and all known details is as follows:
--------------------------------------------------
-------------------------------------

-- Head --
Stacktrace:
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelForma
t(Native
Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat
(WindowsPeerInfo.java:52)

at org.lwjgl.opengl.WindowsDisplay.createWindow(Windo
wsDisplay.java:252)

at org.lwjgl.opengl.Display.createWindow(Display.java
:306)

at org.lwjgl.opengl.Display.create(Display.java:848)

at org.lwjgl.opengl.Display.create(Display.java:757)

at org.lwjgl.opengl.Display.create(Display.java:739)

at bsu.am(SourceFile:523)
at bsu.aj(SourceFile:352)

-- Initialization --
Details:
Stacktrace:
at bsu.a(SourceFile:299)
at net.minecraft.client.main.Main.main(SourceFile:120
)

-- System Details --
Details:
Minecraft Version: 1.8
Operating System: Windows 7 (x86) version 6.1
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 5951680 bytes (5 MB) / 149692416 bytes (142 MB) up to 523501568 bytes (499 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerfor
mance_javaw.exe_minecraft.exe.heapdump
-Xmx512M -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.8
LWJGL: 2.9.1
OpenGL: ~~ERROR~~ RuntimeException: No OpenGL context found in the current thread.
GL Caps:
Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: ~~ERROR~~ NullPointerException: null
Profiler Position: N/A (disabled)

Esy-ce que quelqu'un peut m'aider ?