openGL error

my friend was using my computer the day before today so when i went to play minecraft i had to relog into my account, I did so but when i tried to launch minecraft it crashed during the showing of the mojang logo. I tried playing with different versions but all seemed to have the same problem.
the crash report says there was a runtime exception and that no openGL conext could be found in the thread at org.lwjgl.opengl.GLContext.getCapabilities(GLContext.java:124)
at org.lwjgl.opengl.GL11.glGetError(GL11.java:1299)
at azi.b(SourceFile:824)
at azi.av(SourceFile:884)
at azi.a(SourceFile:328)
at net.minecraft.client.main.Main.main(SourceFile:125)