ERRO download modback

[scaryfacept]

whenever I try to download a modpack it gives this error 

this and the error that appears on the console:

[B#534] java.lang.NoClassDefFoundError: org/eclipse/aether/impl/DefaultServiceLocator$ErrorHandler
[B#534]     at net.technicpack.minecraftcore.install.tasks.HandleVersionFileTask.<init>(HandleVersionFileTask.java:60)
[B#534]     at net.technicpack.launcher.launch.Installer.buildTasksQueue(Installer.java:282)
[B#534]     at net.technicpack.launcher.launch.Installer$1.run(Installer.java:114)
[B#534]     at java.lang.Thread.run(Unknown Source)
[B#534] Caused by: java.lang.ClassNotFoundException: org.eclipse.aether.impl.DefaultServiceLocator$ErrorHandler
[B#534]     at java.net.URLClassLoader.findClass(Unknown Source)
[B#534]     at com.regexlab.j2e.Jar2ExeClassLoader.findClass(Unknown Source)
[B#534]     at java.lang.ClassLoader.loadClass(Unknown Source)
[B#534]     at java.lang.ClassLoader.loadClass(Unknown Source)
[B#534]     ... 4 more
[B#534] Unhandled Exception in Thread[Thread-194,6,main]

 

and this message appears after trying several times:

the modpack does not appear to be installed or is corrupted and is not available for offline play

 

[Lord Ptolemy]

Please provide an uncropped screenshot here or via PM of you logged into the Technic launcher.

[Lord Ptolemy]

Locked. Assuming you're using a cracked launcher.