Log:

 

2013-03-21 15:35:32 [iNFO] [ForgeModLoader] Forge Mod Loader version 5.0.38.600 for Minecraft 1.5.1 loading

2013-03-21 15:35:32 [iNFO] [ForgeModLoader] Java is Java HotSpot Client VM, version 1.6.0_33, running on Windows 7:x86:6.1, installed at C:\Program Files\Java\jre6

2013-03-21 15:35:32 [FINE] [ForgeModLoader] Java classpath at launch is /C:/Users/kathryn/Downloads/MagicLauncher_1.0.0.exe

2013-03-21 15:35:32 [FINE] [ForgeModLoader] Java library path at launch is bin/natives

2013-03-21 15:35:32 [FINE] [ForgeModLoader] Enabling runtime deobfuscation

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] All core mods are successfully located

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] Discovering coremods

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] Found library file argo-small-3.2.jar present and correct in lib dir

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] Found library file guava-14.0-rc3.jar present and correct in lib dir

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] Found library file asm-all-4.1.jar present and correct in lib dir

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] Found library file bcprov-jdk15on-148.jar present and correct in lib dir

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] Found library file deobfuscation_data_1.5.1.zip present and correct in lib dir

2013-03-21 15:35:32 [FINEST] [ForgeModLoader] Downloading file http://files.minecraftforge.net/fmllibs/scala-library.jar

2013-03-21 15:35:32 [iNFO] [ForgeModLoader] Downloading file http://files.minecraftforge.net/fmllibs/scala-library.jar

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] There were errors during initial FML setup. Some files failed to download or were otherwise corrupted. You will need to manually obtain the following files from these download links and ensure your lib directory is clean.

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] *** Download http://files.minecraftforge.net/fmllibs/argo-small-3.2.jar

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] *** Download http://files.minecraftforge.net/fmllibs/guava-14.0-rc3.jar

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] *** Download http://files.minecraftforge.net/fmllibs/asm-all-4.1.jar

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] *** Download http://files.minecraftforge.net/fmllibs/bcprov-jdk15on-148.jar

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] *** Download http://files.minecraftforge.net/fmllibs/deobfuscation_data_1.5.1.zip

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] *** Download http://files.minecraftforge.net/fmllibs/scala-library.jar

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] <===========>

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] The following is the errors that caused the setup to fail. They may help you diagnose and resolve the issue

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] java.net.SocketException: Connection reset

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] <<< ==== >>>

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] The following is diagnostic information for developers to review.

2013-03-21 15:36:40 [sEVERE] [ForgeModLoader] Error details

java.lang.RuntimeException: java.net.SocketException: Connection reset

at cpw.mods.fml.relauncher.RelaunchLibraryManager.performDownload(RelaunchLibraryManager.java:597)

at cpw.mods.fml.relauncher.RelaunchLibraryManager.downloadFile(RelaunchLibraryManager.java:532)

at cpw.mods.fml.relauncher.RelaunchLibraryManager.handleLaunch(RelaunchLibraryManager.java:165)

at cpw.mods.fml.relauncher.FMLRelauncher.setupHome(FMLRelauncher.java:172)

at cpw.mods.fml.relauncher.FMLRelauncher.relaunchClient(FMLRelauncher.java:104)

at cpw.mods.fml.relauncher.FMLRelauncher.handleClientRelaunch(FMLRelauncher.java:38)

at net.minecraft.client.Minecraft.main(Minecraft.java:2228)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.lang.reflect.Method.invoke(Unknown Source)

at magic.launcher.Launcher.main(Unknown Source)

Caused by: java.net.SocketException: Connection reset

at java.net.SocketInputStream.read(Unknown Source)

at java.io.BufferedInputStream.fill(Unknown Source)

at java.io.BufferedInputStream.read1(Unknown Source)

at java.io.BufferedInputStream.read(Unknown Source)

at sun.net.www.MeteredStream.read(Unknown Source)

at java.io.FilterInputStream.read(Unknown Source)

at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(Unknown Source)

at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(Unknown Source)

at cpw.mods.fml.relauncher.RelaunchLibraryManager.performDownload(RelaunchLibraryManager.java:575)

... 11 more

 

 

 

I have a rather slow connection (188 kbps down/74 kbps up as of check at 3:44 PM my time), but I haven't had this problem until 1.5 came out.

 

1.5.1 installed. All mods (OptiFine, Rei's Minimap) updated to 1.5.1, then disabled in Magic Launcher.

how do I do that?

Boom. Problem solved. Feel free to close the thread now