I'm trying to download Forge 1.12.2 (recommended version) on my Mac. I have the most recent JDK installed and I'm able to download Forge just fine. The problem is that the installation gets stuck on the same step every time I try to install Forge. Here is the error message:

 

java.net.preferIPv4Stack=true
Considering library net.minecraftforge:forge:1.12.2-14.23.5.2847: Not Downloading {Wrong Side}
Considering library net.minecraft:launchwrapper:1.12: Not Downloading {Wrong Side}
Considering library org.ow2.asm:asm-all:5.2
Considering library org.jline:jline:3.5.1: Not Downloading {Wrong Side}
Considering library net.java.dev.jna:jna:4.4.0: Not Downloading {Wrong Side}
Considering library com.typesafe.akka:akka-actor_2.11:2.3.3
Checking "/Users/wilsonconn/Library/Application Support/minecraft/libraries/com/typesafe/akka/akka-actor_2.11/2.3.3/akka-actor_2.11-2.3.3.jar" internal checksums
    checksums.sha1 was not found, validation failed
Downloading library com.typesafe.akka:akka-actor_2.11:2.3.3
Unpacking packed file akka-actor_2.11-2.3.3.jar.pack.xz
  Signed
  Checksum Length: 140942
  Total Length:    2606968
  Temp File:       /var/folders/0q/y3hxyq313yq_44ct4j3592nh0000gp/T/art800974051921681250.pack
Exception in thread "main" java.lang.reflect.InvocationTargetException
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:564)
    at net.minecraftforge.installer.Java6Gate.main(Java6Gate.java:48)
Caused by: java.lang.NoClassDefFoundError: java/util/jar/Pack200
    at net.minecraftforge.installer.DownloadUtils.unpackLibrary(DownloadUtils.java:253)
    at net.minecraftforge.installer.DownloadUtils.downloadInstalledLibraries(DownloadUtils.java:89)
    at net.minecraftforge.installer.ClientInstall.run(ClientInstall.java:131)
    at net.minecraftforge.installer.InstallerAction.run(InstallerAction.java:43)
    at net.minecraftforge.installer.InstallerPanel.run(InstallerPanel.java:406)
    at net.minecraftforge.installer.SimpleInstaller.launchGui(SimpleInstaller.java:168)
    at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:54)
    ... 5 more
Caused by: java.lang.ClassNotFoundException: java.util.jar.Pack200
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:602)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
    ... 12 more

 

If you can help, I'd really appreciate it. Thanks
 

 

 

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