Crashes when press Play

After pressing the Play button, the launcher will download the version and launch the game as normal. But after launching, the launcher will pop open and display Game Output instead of launching game.

Still crashes if I Switch User or log in again. I have checked location of Java and matched with the launcher, but still crashes.

The Game Output displays:

[21:38:13] [Client thread/INFO]: Setting user: PotatoMaster101
[21:38:13] [Client thread/INFO]: (Session ID is token:7de0a96198644abfb98620b2e4720cee:cb2671d590b84dfe9b1c73683d451d1a)
Exception in thread "Client thread" com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1
at com.google.gson.Gson.fromJson(Gson.java:815)
at com.google.gson.Gson.fromJson(Gson.java:768)
at rx.b(SourceFile:148)
at rx.<init>(SourceFile:42)
at net.minecraft.server.MinecraftServer.<init>(SourceFile:155)
at cya.<init>(SourceFile:40)
at bso.<init>(SourceFile:280)
at net.minecraft.client.main.Main.main(SourceFile:120)
Caused by: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1
at com.google.gson.stream.JsonReader.beginArray(JsonReader.java:338)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:79)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:60)
at com.google.gson.Gson.fromJson(Gson.java:803)
... 7 more