Clicking on Multiplayer crashes immediately, tried reinstalling a few times, even tries the standalone version. Nothing does it. Keeps outputing:

---- Minecraft Crash Report ----
// Quite honestly, I wouldn't worry myself about that.

Time: 19:54 04/05/15
Description: Rendering screen

java.lang.IllegalArgumentException: bad Base64 input character at 4416: 0 (decimal)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:247)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:197)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:188)
at azk.c(SourceFile:212)
at azk.a(SourceFile:145)
at awd.a(SourceFile:25)
at awi.b(SourceFile:412)
at awi.a(SourceFile:211)
at azh.a(SourceFile:291)
at bfk.a(SourceFile:1039)
at ave.av(SourceFile:914)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at io.netty.handler.codec.base64.Base64.decode(Base64.java:247)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:197)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:188)
at azk.c(SourceFile:212)
at azk.a(SourceFile:145)
at awd.a(SourceFile:25)
at awi.b(SourceFile:412)
at awi.a(SourceFile:211)
at azh.a(SourceFile:291)

– Screen render details –
Details:
Screen name: azh
Mouse location: Scaled: (161, 146). Absolute: (322, 186)
Screen size: Scaled: (427, 240). Absolute: (854, 480). Scale factor of 2
Stacktrace:
at bfk.a(SourceFile:1039)
at ave.av(SourceFile:914)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)

– System Details –
Details:
Minecraft Version: 1.8.4
Operating System: Windows 8.1 (amd64) version 6.3
CPU: 8x Intel(R) Core(TM) i7-4790K CPU @ 4.00GHz
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 86978360 bytes (82 MB) / 255066112 bytes (243 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.8.4
LWJGL: 2.9.4
OpenGL: GeForce GTX 970/PCIe/SSE2 GL version 4.5.0 NVIDIA 347.88, NVIDIA Corporation
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

Using VBOs: Yes
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (US)
Profiler Position: N/A (disabled)