Can't play on my server on certain levels?
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Anytime I try to play levels on my server, except for one, my friend and I get errors. They're all generated from Omen so I don't know why only one will work.
WARNING: Found unknown Windows version: Windows 7
Attempting to use default windows plug-in.
java.lang.NullPointerException
at com.mojang.minecraft.b.j.a(Unknown Source)
at com.mojang.minecraft.l.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
org.lwjgl.opengl.OpenGLException: Invalid operation (1282)
at org.lwjgl.opengl.Util.checkGLError(Util.java:54)
at org.lwjgl.opengl.Display.swapBuffers(Display.java:640)
at org.lwjgl.opengl.Display.update(Display.java:660)
at com.mojang.minecraft.l.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at com.mojang.minecraft.b.j.a(Unknown Source)
at com.mojang.minecraft.l.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at com.mojang.minecraft.b.j.a(Unknown Source)
at com.mojang.minecraft.l.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
########## GL ERROR ##########
@ Pre render
1282: Invalid operation
I'm not sure about my friend's errors but I know he gets a Nullpointer one too..