Hopper: Unhandled exception - error reading zip file

Unhandled exception
	at java.util.zip.ZipFile$2.nextElement(Unknown Source)
	at java.util.zip.ZipFile$2.nextElement(Unknown Source)
	at bqi.c(SourceFile:69)
	at bqx.a(SourceFile:34)
	at bqx.a(SourceFile:89)
	at azd.b(SourceFile:488)
	at bgh.a(SourceFile:151)
	at bcd.a(SourceFile:172)
	at bgh.a(SourceFile:158)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)

---- Minecraft Crash Report ----
// Hey, that tickles! Hehehe!

Time: 25/10/13 21:55
Description: Updating screen events

java.util.zip.ZipError: jzentry == 0,
 jzfile = 1267272912,
 total = 1596,
 name = C:\Users\Mum\AppData\Roaming\.minecraft\resourcepacks\Alpha Pack.zip,
 i = 1,
 message = error reading zip file
	at java.util.zip.ZipFile$2.nextElement(Unknown Source)
	at java.util.zip.ZipFile$2.nextElement(Unknown Source)
	at bqi.c(SourceFile:69)
	at bqx.a(SourceFile:34)
	at bqx.a(SourceFile:89)
	at azd.b(SourceFile:488)
	at bgh.a(SourceFile:151)
	at bcd.a(SourceFile:172)
	at bgh.a(SourceFile:158)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)
	at azd.o(SourceFile:1303)
	at azd.ad(SourceFile:753)
	at azd.e(SourceFile:704)
	at net.minecraft.client.main.Main.main(SourceFile:103)


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

-- Head --
Stacktrace:
	at java.util.zip.ZipFile$2.nextElement(Unknown Source)
	at java.util.zip.ZipFile$2.nextElement(Unknown Source)
	at bqi.c(SourceFile:69)
	at bqx.a(SourceFile:34)
	at bqx.a(SourceFile:89)
	at azd.b(SourceFile:488)
	at bgh.a(SourceFile:151)
	at bcd.a(SourceFile:172)
	at bgh.a(SourceFile:158)
	at bcd.d(SourceFile:236)
	at bcd.k(SourceFile:211)

-- Affected screen --
Details:
	Screen name: bgh
Stacktrace:
	at azd.o(SourceFile:1303)
	at azd.ad(SourceFile:753)
	at azd.e(SourceFile:704)
	at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
	Minecraft Version: 1.7.2
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.6.0_21, Sun Microsystems Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Sun Microsystems Inc.
	Memory: 130610344 bytes (124 MB) / 491388928 bytes (468 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	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: 1.7.2
	LWJGL: 2.9.0
	OpenGL: AMD M880G with ATI Mobility Radeon HD 4250                GL version 3.3.10179 Compatibility Profile Context, ATI Technologies Inc.
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: [Alpha Pack.zip, Definitance_2.zip, Misa.zip]
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: ~~ERROR~~ NullPointerException: null
	Anisotropic Filtering: Off (1)