I have the same problem because I just updated to 3.1.3 but mine is giving me this when my server tries to launch and it stops at ...6more.
C:\Users\hidden name\appdata\Roaming\.techniclauncher>java -Xmx1G -Xms1G -jar
Tekkit.jar nogui
182 recipes
27 achievements
19:37:54 [iNFO] Starting minecraft server version 1.2.5
19:37:54 [iNFO] Attempting early MinecraftForge initialization
19:37:54 [iNFO] Completed early MinecraftForge initialization
19:37:54 [iNFO] Forge Mod Loader version 2.2.91.182 for Minecraft 1.2.5 loading
19:37:55 [iNFO] Loading mods from C:\Users\Ketron Family\AppData\Roaming\.techni
clauncher\mods
19:37:55 [iNFO] Directory weaponmod contained no mods
19:37:55 [iNFO] Forge Mod Loader has loaded 49 mods
19:37:55 [iNFO] MinecraftForge v3.3.8.152 Initialized
19:37:55 [iNFO] MinecraftForge v3.3.8.152 Initialized
19:37:55 [iNFO] [WeaponMod] Properties file read succesfully!
19:37:55 [WARNING] Configuration for mod_ComputerCraft.enableAPI_http found valu
e 0 outside acceptable range 4.9E-324,1.7976931348623157E308
19:37:55 [iNFO] Loading ComputerCraft: To change block IDs, modify config/mod_Co
mputerCraft.cfg
19:37:55 [iNFO] ComputerCraft: computerBlockID 207
19:37:55 [iNFO] ComputerCraft: diskDriveBlockID 208
19:37:55 [iNFO] ComputerCraft: diskItemID 4000
19:37:55 [iNFO] CONFLICT @ -49 item slot already occupied by dan200.computer.sha
red.ItemComputer@1475116 while adding net.minecraft.server.ItemBlock@11c8643
19:37:55 [iNFO] ComputerCraft: Searching for RedPowerLib...
19:37:55 [iNFO] ComputerCraft: RedPowerLib and methods located.
19:37:55 [iNFO] CONFLICT @ -48 item slot already occupied by dan200.computer.sha
red.ItemPeripheral@1bd9ca9 while adding net.minecraft.server.ItemBlock@17858a9
19:37:55 [WARNING] Configuration for mod_ComputerCraft.enableAPI_http found valu
e 0 outside acceptable range 4.9E-324,1.7976931348623157E308
19:37:55 [iNFO] Loading ComputerCraft: To change block IDs, modify config/mod_Co
mputerCraft.cfg
19:37:55 [iNFO] ComputerCraft: computerBlockID 207
19:37:55 [iNFO] ComputerCraft: diskDriveBlockID 208
19:37:55 [iNFO] ComputerCraft: diskItemID 4000
19:37:55 [sEVERE] cpw.mods.fml.common.LoaderException: java.lang.IllegalArgument
Exception: Slot 207 is already occupied by dan200.computer.shared.BlockComputer@
13a1b2 when adding dan200.computer.shared.BlockComputer@dccf02
19:37:55 [sEVERE] at cpw.mods.fml.common.modloader.ModLoaderModContainer.p
reInit(ModLoaderModContainer.java:114)
19:37:55 [sEVERE] at cpw.mods.fml.common.Loader.preModInit(Loader.java:235
)
19:37:55 [sEVERE] at cpw.mods.fml.common.Loader.loadMods(Loader.java:607)
19:37:55 [sEVERE] at cpw.mods.fml.server.FMLBukkitHandler.onPreLoad(FMLBuk
kitHandler.java:134)
19:37:55 [sEVERE] at net.minecraft.server.MinecraftServer.init(MinecraftSe
rver.java:125)
19:37:55 [sEVERE] at net.minecraft.server.MinecraftServer.run(MinecraftSer
ver.java:428)
19:37:55 [sEVERE] at net.minecraft.server.ThreadServerApplication.run(Sour
ceFile:492)
19:37:55 [sEVERE] Caused by: java.lang.IllegalArgumentException: Slot 207 is alr
eady occupied by dan200.computer.shared.BlockComputer@13a1b2 when adding dan200.
computer.shared.BlockComputer@dccf02
19:37:55 [sEVERE] at net.minecraft.server.Block.<init>(Block.java:181)
19:37:55 [sEVERE] at net.minecraft.server.BlockContainer.<init>(BlockConta
iner.java:6)
19:37:56 [sEVERE] at dan200.computer.shared.BlockComputerBase.<init>(Block
ComputerBase.java:24)
19:37:56 [sEVERE] at dan200.computer.shared.BlockComputer.<init>(BlockComp
uter.java:19)
19:37:56 [sEVERE] at net.minecraft.server.mod_ComputerCraft.<init>(mod_Com
puterCraft.java:74)
19:37:56 [sEVERE] at sun.reflect.NativeConstructorAccessorImpl.newInstance
0(Native Method)
19:37:56 [sEVERE] at sun.reflect.NativeConstructorAccessorImpl.newInstance
(Unknown Source)
19:37:56 [sEVERE] at sun.reflect.DelegatingConstructorAccessorImpl.newInst
ance(Unknown Source)
19:37:56 [sEVERE] at java.lang.reflect.Constructor.newInstance(Unknown Sou
rce)
19:37:56 [sEVERE] at java.lang.Class.newInstance0(Unknown Source)
19:37:56 [sEVERE] at java.lang.Class.newInstance(Unknown Source)
19:37:56 [sEVERE] at cpw.mods.fml.common.modloader.ModLoaderModContainer.p
reInit(ModLoaderModContainer.java:107)
19:37:56 [sEVERE] ... 6 more
19:37:56 [sEVERE] Unexpected exception
cpw.mods.fml.common.LoaderException: java.lang.IllegalArgumentException: Slot 20
7 is already occupied by dan200.computer.shared.BlockComputer@13a1b2 when adding
dan200.computer.shared.BlockComputer@dccf02
at cpw.mods.fml.common.modloader.ModLoaderModContainer.preInit(ModLoader
ModContainer.java:114)
at cpw.mods.fml.common.Loader.preModInit(Loader.java:235)
at cpw.mods.fml.common.Loader.loadMods(Loader.java:607)
at cpw.mods.fml.server.FMLBukkitHandler.onPreLoad(FMLBukkitHandler.java:
134)
at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:125)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:428)
at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.IllegalArgumentException: Slot 207 is already occupied by d
an200.computer.shared.BlockComputer@13a1b2 when adding dan200.computer.shared.Bl
ockComputer@dccf02
at net.minecraft.server.Block.<init>(Block.java:181)
at net.minecraft.server.BlockContainer.<init>(BlockContainer.java:6)
at dan200.computer.shared.BlockComputerBase.<init>(BlockComputerBase.jav
a:24)
at dan200.computer.shared.BlockComputer.<init>(BlockComputer.java:19)
at net.minecraft.server.mod_ComputerCraft.<init>(mod_ComputerCraft.java:
74)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Sou
rce)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at java.lang.Class.newInstance0(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at cpw.mods.fml.common.modloader.ModLoaderModContainer.preInit(ModLoader
ModContainer.java:107)
... 6 more
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