Crashlog with Java JRE 8 Update 51 for x64 bits

My launcher is able to run minecraft with java 32 bits but when installed a java 64 bits my launcher crash to this. I'm also using an Optifine version. I didn't tried yet to test other versions cause I don't think could be a minecraft version issue. 

ISSUE DEVELOPMENT CONSOLE:

[14:49:20 SEVERE]: Fatal error launching game. Report this to http://bugs.mojang.com please!
java.io.FileNotFoundException: File 'C:\Users\Usuario\AppData\Roaming\.minecraft\assets\indexes\legacy.json' does not exist
    at org.apache.commons.io.FileUtils.openInputStream(FileUtils.java:299)
    at org.apache.commons.io.FileUtils.readFileToString(FileUtils.java:1711)
    at net.minecraft.launcher.Launcher.R(Unknown Source)
    at net.minecraft.launcher.Launcher.W(Unknown Source)
    at net.minecraft.launcher.game.a.launchGame(Unknown Source)
    at com.mojang.launcher.game.runner.AbstractGameRunner.onDownloadJobFinished(Unknown Source)
    at com.mojang.launcher.updater.download.DownloadJob.popAndDownload(Unknown Source)
    at com.mojang.launcher.updater.download.DownloadJob.access$000(Unknown Source)
    at com.mojang.launcher.updater.download.DownloadJob$1.run(Unknown Source)
    at java.util.concurrent.Executors$RunnableAdapter.call(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)

[14:49:20 SEVERE]: Game ended with bad state (exit code 1)

 

WITHOUT OPTIFINE
Caused by: java.lang.ClassNotFoundException: net.minecraft.client.main.Main

 

WITH OPTIFINE
Caused by: java.lang.ClassNotFoundException: net.minecraft.launchwrapper.Launch