game crashes when trying to load save game

[20:16:52 FATAL]: Fatal error launching game. Report this to http://bugs.mojang.com please!
java.io.FileNotFoundException: File 'C:\Users\Darth Vader\AppData\Roaming\.minecraft\assets\indexes\legacy.json' does not exist
at org.apache.commons.io.FileUtils.openInputStream(FileUtils.java:299) ~[launcher.jar:1.6.61]
at org.apache.commons.io.FileUtils.readFileToString(FileUtils.java:1711) ~[launcher.jar:1.6.61]
at net.minecraft.launcher.Launcher.cleanupOrphanedAssets(Launcher.java:254) ~[launcher.jar:1.6.61]
at net.minecraft.launcher.Launcher.performCleanups(Launcher.java:496) ~[launcher.jar:1.6.61]
at net.minecraft.launcher.game.MinecraftGameRunner.launchGame(MinecraftGameRunner.java:231) ~[launcher.jar:1.6.61]
at com.mojang.launcher.game.runner.AbstractGameRunner.onDownloadJobFinished(AbstractGameRunner.java:186) [launcher.jar:1.6.61]
at com.mojang.launcher.updater.download.DownloadJob.popAndDownload(DownloadJob.java:122) [launcher.jar:1.6.61]
at com.mojang.launcher.updater.download.DownloadJob.access$000(DownloadJob.java:12) [launcher.jar:1.6.61]
at com.mojang.launcher.updater.download.DownloadJob$1.run(DownloadJob.java:86) [launcher.jar:1.6.61]
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_91]
at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_91]
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [?:1.8.0_91]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [?:1.8.0_91]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_91]
[20:17:08 ERROR]: Game ended with bad state (exit code 255)
[20:17:08 INFO]: Ignoring visibility rule and showing launcher due to a game crash
[20:17:08 INFO]: Deleting C:\Users\Darth Vader\AppData\Roaming\.minecraft\versions\1.10.2\1.10.2-natives-262909021645