Salut, voila un bon matin, en fait minecraft.exe veut pas se lancer, il me dise l'erreur de la carte graphique, alors que avant sa marché parfaitement, a votre avis, d'ou viens le bug ? merci d'avance

De la carte graphique ?
C'est quoi le message exact ?

attend bouge pas

Bad video card drivers!
-----------------------

Minecraft was unable to start because it failed to find an accelerated OpenGL mode.
This can usually be fixed by updating the video card drivers.

--- BEGIN ERROR REPORT 7fe0271 --------
Generated 19/10/11 13:54

Minecraft: Minecraft Beta 1.8.1
OS: Windows Vista (x86) version 6.0
Java: 1.6.0_27, Sun Microsystems Inc.
VM: Java HotSpot(TM) Client VM (mixed mode), Sun Microsystems Inc.
LWJGL: 2.4.2
[failed to get system properties (java.lang.NullPointerException)]

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:185)
at
org.lwjgl.opengl.Display.createWindow(Display.java
:311)
at
org.lwjgl.opengl.Display.create(Display.java:856)

at
org.lwjgl.opengl.Display.create(Display.java:784)

at
org.lwjgl.opengl.Display.create(Display.java:765)

at net.minecraft.client.Minecraft.a(SourceFile:233)
at
net.minecraft.client.Minecraft.run(SourceFile:629)

at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT c6f542ad ----------

"This can usually be fixed by updating the video card drivers. "
Essaye de mettre à jour les drivers de ta carte graphique. Google pourra t'aider.