---- Minecraft Crash Report ----
// I feel sad now

Time: 01-03-2014 9:34
Description: Rendering screen

java.lang.IllegalArgumentException: bad Base64 input character at 2744: 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 bhc.b(SourceFile:155)
at bhc.a(SourceFile:130)
at bbd.a(SourceFile:26)
at bbi.b(SourceFile:382)
at bbi.a(SourceFile:259)
at bgz.a(SourceFile:283)
at bms.b(SourceFile:852)
at azl.ah(SourceFile:784)
at azl.f(SourceFile:711)
at net.minecraft.client.main.Main.main(SourceFile:148)

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 bhc.b(SourceFile:155)
at bhc.a(SourceFile:130)
at bbd.a(SourceFile:26)
at bbi.b(SourceFile:382)
at bbi.a(SourceFile:259)
at bgz.a(SourceFile:283)

– Screen render details –
Details:
Screen name: bgz
Mouse location: Scaled: (232, 147). Absolute: (464, 184)
Screen size: Scaled: (427, 240). Absolute: (854, 480). Scale factor of 2
Stacktrace:
at bms.b(SourceFile:852)
at azl.ah(SourceFile:784)
at azl.f(SourceFile:711)
at net.minecraft.client.main.Main.main(SourceFile:148)

– System Details –
Details:
Minecraft Version: 1.7.5
Operating System: Windows XP (x86) version 5.1
Java Version: 1.7.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
Memory: 33131184 bytes (31 MB) / 69275648 bytes (66 MB) up to 518979584 bytes (494 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.7.5
LWJGL: 2.9.1
OpenGL: Radeon X1650 Series GL version 2.1.8494 Release, ATI Technologies Inc.
GL Caps: Using GL 1.3 multitexturing.
Using framebuffer objects because ARB_framebuffer_object is supported and separate blending is supported.
Anisotropic filtering is supported and maximum anisotropy is 16.
Shaders are available because OpenGL 2.1 is supported.

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)
Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Anisotropic Filtering: Off (1)