Searched on Google with the first line of a JAVA stack trace?

We can recommend more relevant solutions and speed up debugging when you paste your entire stack trace with the exception message. Try a sample exception.

Recommended solutions based on your search

Solutions on the web

via Arqade by ReallyGoodPie
, 1 year ago
Version '1.6.1' is already tracked
via stackexchange.com by Unknown author, 2 years ago
java.lang.IllegalArgumentException: Version '1.6.1' is already tracked	at net.minecraft.launcher.updater.VersionList.addVersion(VersionList.java:91)	at net.minecraft.launcher.updater.LocalVersionList.refreshVersions(LocalVersionList.java:44)	at net.minecraft.launcher.updater.VersionManager.refreshVersions(VersionManager.java:47)	at net.minecraft.launcher.Launcher$2.run(Launcher.java:164)	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)	at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)	at java.util.concurrent.FutureTask.run(Unknown Source)	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)	at java.lang.Thread.run(Unknown Source)