Yosemite install failure: restarts when downloading

Trying to Install Yosemite: When install Yosemite from Appstore the Imac restarts and gives this error report: I have recently installed more RAM and it seems to work fine until i tried to download system upgrade.

Anonymous UUID: FDDCD74F-41C0-DC5F-B26F-96D026BD96EC

Mon Aug 31 09:50:53 2015

panic(cpu 0 caller 0xffffff801b8f0adf): "Free of uninitialized label\n"@/SourceCache/xnu/xnu-2422.115.4/security/mac_label.c:79

Backtrace (CPU 0), Frame : Return Address

0xffffff827738bd60 : 0xffffff801b422f79

0xffffff827738bde0 : 0xffffff801b8f0adf

0xffffff827738be00 : 0xffffff801b8f2da5

0xffffff827738be20 : 0xffffff801b445696

0xffffff827738be50 : 0xffffff801b448789

0xffffff827738be80 : 0xffffff801b4485ee

0xffffff827738beb0 : 0xffffff801b420b63

0xffffff827738bee0 : 0xffffff801b4dca73

0xffffff827738bf00 : 0xffffff801b4f3942

BSD process name corresponding to current thread: loginwindow

Mac OS version:

13F34

Kernel version:

Darwin Kernel Version 13.4.0: Sun Aug 17 19:50:11 PDT 2014; root:xnu-2422.115.4~1/RELEASE_X86_64

Kernel UUID: 9477416E-7BCA-3679-AF97-E1EAAD3DD5A0

Kernel slide: 0x000000001b200000

Kernel text base: 0xffffff801b400000

System model name: iMac11,2 (Mac-F2238AC8)

System uptime in nanoseconds: 1909327845321

last loaded kext at 1424672517046: com.apple.filesystems.msdosfs 1.9 (addr 0xffffff7f9d71d000, size 65536)

last unloaded kext at 1863092801206: com.apple.filesystems.msdosfs 1.9 (addr 0xffffff7f9d71d000, size 57344)

loaded kexts:

com.apple.driver.AppleBluetoothMultitouch 80.14

com.apple.driver.AudioAUUC 1.60

com.apple.driver.AGPM 100.14.34

com.apple.filesystems.autofs 3.0

com.apple.driver.AppleMikeyHIDDriver 124

com.apple.driver.AppleMikeyDriver 2.6.3f4

com.apple.driver.AppleHWSensor 1.9.5d0

com.apple.driver.AppleHDA 2.6.3f4

com.apple.driver.AppleUpstreamUserClient 3.5.13

com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport 4.2.7f3

com.apple.kext.AMDFramebuffer 1.2.4

com.apple.iokit.IOUserEthernet 1.0.0d1

com.apple.driver.AppleBacklight 170.4.11

com.apple.driver.AppleMCCSControl 1.2.5

com.apple.driver.ACPI_SMC_PlatformPlugin 1.0.0

com.apple.driver.AppleLPC 1.7.0

com.apple.iokit.IOBluetoothSerialManager 4.2.7f3

com.apple.Dont_Steal_Mac_OS_X 7.0.0

com.apple.driver.AppleHWAccess 1

com.apple.ATIRadeonX2000 8.2.4

com.apple.kext.AMD4600Controller 1.2.4

com.apple.driver.AppleUSBCardReader 3.4.1

com.apple.driver.AppleIRController 325.7

com.apple.AppleFSCompression.AppleFSCompressionTypeDataless 1.0.0d1

com.apple.AppleFSCompression.AppleFSCompressionTypeLZVN 1.0.0d1

com.apple.AppleFSCompression.AppleFSCompressionTypeZlib 1.0.0d1

com.apple.BootCache 35

com.apple.iokit.SCSITaskUserClient 3.6.7

com.apple.driver.AppleUSBHub 683.4.0

com.apple.driver.XsanFilter 404

com.apple.iokit.IOAHCIBlockStorage 2.6.0

com.apple.driver.AppleFWOHCI 5.0.2

com.apple.driver.AirPort.Atheros40 700.74.5

com.apple.driver.AppleUSBEHCI 660.4.0

com.apple.driver.AppleAHCIPort 3.0.5

com.apple.iokit.AppleBCM5701Ethernet 3.8.1b2

com.apple.driver.AppleRTC 2.0

com.apple.driver.AppleACPIButtons 2.0

com.apple.driver.AppleHPET 1.8

com.apple.driver.AppleSMBIOS 2.1

com.apple.driver.AppleACPIEC 2.0

com.apple.driver.AppleAPIC 1.7

com.apple.driver.AppleIntelCPUPowerManagementClient 217.92.1

com.apple.nke.applicationfirewall 153

com.apple.security.quarantine 3

com.apple.driver.AppleIntelCPUPowerManagement 217.92.1

com.apple.driver.AppleBluetoothHIDKeyboard 170.15

com.apple.driver.AppleHIDKeyboard 170.15

com.apple.driver.IOBluetoothHIDDriver 4.2.7f3

com.apple.driver.AppleMultitouchDriver 245.13.1

com.apple.kext.triggers 1.0

com.apple.driver.DspFuncLib 2.6.3f4

com.apple.vecLib.kext 1.0.0

com.apple.iokit.IOAudioFamily 1.9.7fc2

com.apple.kext.OSvKernDSPLib 1.14

com.apple.iokit.IOBluetoothHostControllerUSBTransport 4.2.7f3

com.apple.iokit.IOSurface 91.1

com.apple.driver.AppleBacklightExpert 1.0.4

com.apple.driver.AppleSMBusController 1.0.12d1

com.apple.iokit.IOFireWireIP 2.2.6

com.apple.driver.AppleHDAController 2.6.3f4

com.apple.iokit.IOHDAFamily 2.6.3f4

com.apple.driver.AppleSMBusPCI 1.0.12d1

com.apple.driver.IOPlatformPluginLegacy 1.0.0

com.apple.driver.IOPlatformPluginFamily 5.7.1d6

com.apple.iokit.IOSerialFamily 10.0.7

com.apple.iokit.IOBluetoothFamily 4.2.7f3

com.apple.driver.AppleSMC 3.1.8

com.apple.iokit.IONDRVSupport 2.4.1

com.apple.kext.AMDSupport 1.2.4

com.apple.AppleGraphicsDeviceControl 3.6.22

com.apple.iokit.IOGraphicsFamily 2.4.1

com.apple.iokit.IOSCSIBlockCommandsDevice 3.6.7

com.apple.iokit.IOUSBMassStorageClass 3.6.0

com.apple.iokit.IOUSBHIDDriver 660.4.0

com.apple.driver.AppleUSBMergeNub 650.4.0

com.apple.driver.AppleUSBComposite 656.4.1

com.apple.iokit.IOSCSIMultimediaCommandsDevice 3.6.7

com.apple.iokit.IOBDStorageFamily 1.7

com.apple.iokit.IODVDStorageFamily 1.7.1

com.apple.iokit.IOCDStorageFamily 1.7.1

com.apple.iokit.IOAHCISerialATAPI 2.6.1

com.apple.iokit.IOSCSIArchitectureModelFamily 3.6.7

com.apple.iokit.IOUSBUserClient 660.4.2

com.apple.iokit.IOFireWireFamily 4.5.5

com.apple.iokit.IO80211Family 640.36

com.apple.iokit.IOAHCIFamily 2.6.5

com.apple.iokit.IOEthernetAVBController 1.0.3b4

com.apple.driver.mDNSOffloadUserClient 1.0.1b5

com.apple.iokit.IONetworkingFamily 3.2

com.apple.iokit.IOUSBFamily 686.4.1

com.apple.driver.AppleEFINVRAM 2.0

com.apple.driver.AppleEFIRuntime 2.0

com.apple.iokit.IOHIDFamily 2.0.0

com.apple.iokit.IOSMBusFamily 1.1

com.apple.security.sandbox 278.11.1

com.apple.kext.AppleMatch 1.0.0d1

com.apple.security.TMSafetyNet 7

com.apple.driver.AppleKeyStore 2

com.apple.driver.DiskImages 371.1

com.apple.iokit.IOStorageFamily 1.9

com.apple.iokit.IOReportFamily 23

com.apple.driver.AppleFDEKeyStore 28.30

com.apple.driver.AppleACPIPlatform 2.0

com.apple.iokit.IOPCIFamily 2.9

com.apple.iokit.IOACPIFamily 1.4

com.apple.kec.corecrypto 1.0

com.apple.kec.pthread 1