[MCL-464] Unexpected exception refreshing version list / Play button grey

Fix: Reinstalling Minecraft following this guide http://hopper.minecraft.net/help/reinstalling-minecraft

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I cant login so i cant play the game.
if i start offline i cant play as well
PS: i play on dev 0.9.3

Launcher 0.9.3 (Dev) (through bootstrap 3) started on windows...
System.getProperty('os.name') == 'Windows 8'
System.getProperty('os.version') == '6.2'
System.getProperty('os.arch') == 'amd64'
System.getProperty('java.version') == '1.7.0_21'
System.getProperty('java.vendor') == 'Oracle Corporation'
Loaded 3 profile(s); selected '1.5.2'
Unexpected exception refreshing version list
java.lang.IllegalArgumentException: Version '13w24b' 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$2.run(Launcher.java:163)
	at java.util.concurrent.Executors$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)

Delta time to compare resources: 752 ms 
Download job 'Resources' skipped as there are no files to download
Job 'Resources' finished successfully

~~MCL-1294~~

Unexpected exception refreshing version list
java.lang.NullPointerException
	at net.minecraft.launcher.updater.VersionList.addVersion(VersionList.java:90)
	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$2.run(Launcher.java:166)
	at java.util.concurrent.Executors$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)