Been having almost exactly the same issue with my late 2009, 27" iMac. It is booting in safe mode but not in normal mode where it does not get past the apple logo. Have tried many suggestions around the forums and not any closer (yet). It started about 3 weeks ago and I am running Mavericks 10.9.2.
I have ran the 4 steps suggested in this post. Steps 1,2 and 4 give nothing. Step 3 provides the following - Thank you in advance for any guidance you might be able to give around where my issues lie.
/Library/Components:
/Library/Extensions:
ATTOCelerityFC8.kext
ATTOExpressSASHBA2.kext
ATTOExpressSASRAID2.kext
ArcMSR.kext
CalDigitHDProDrv.kext
HighPointIOP.kext
HighPointRR.kext
PromiseSTEX.kext
SoftRAID.kext
/Library/Frameworks:
AEProfiling.framework
AERegistration.framework
Adobe AIR.framework
AudioMixEngine.framework
HPPml.framework
HPServicesInterface.framework
HPSmartX.framework
MacFUSE.framework
NyxAudioAnalysis.framework
PluginManager.framework
Snapfish.framework
iTunesLibrary.framework
/Library/Input Methods:
/Library/Internet Plug-Ins:
AdobePDFViewer.plugin
CitrixICAClientPlugIn.plugin
Default Browser.plugin
Flash Player.plugin
Google Earth Web Plug-in.plugin
JavaAppletPlugin.plugin
OfficeLiveBrowserPlugin.plugin
Quartz Composer.webplugin
QuickTime Plugin.plugin
Unity Web Player.plugin
Unused
flashplayer.xpt
iPhotoPhotocast.plugin
nsIQTScriptablePlugin.xpt
/Library/Keyboard Layouts:
/Library/LaunchAgents:
com.adobe.AAM.Updater-1.0.plist
com.adobe.CS5ServiceManager.plist
com.citrix.AuthManager_Mac.plist
com.citrix.ReceiverHelper.plist
com.citrix.ServiceRecords.plist
com.micromat.TechToolProAgent.plist
/Library/LaunchDaemons:
com.adobe.SwitchBoard.plist
com.adobe.fpsaud.plist
com.crashplan.engine.plist
com.mfluent.mBoxMail.plist
com.micromat.TechToolProDaemon.plist
com.stclairsoft.AppTamerAgent.plist
/Library/PreferencePanes:
Box Sync.prefPane
Flash Player.prefPane
/Library/PrivilegedHelperTools:
Google Drive Icon Helper
com.stclairsoft.AppTamerAgent
/Library/QuickLook:
GBQLGenerator.qlgenerator
ParallelsQL.qlgenerator
iBooksAuthor.qlgenerator
iWork.qlgenerator
/Library/QuickTime:
AppleIntermediateCodec.component
AppleMPEG2Codec.component
/Library/ScriptingAdditions:
Adobe Unit Types.osax
/Library/Spotlight:
GBSpotlightImporter.mdimporter
Microsoft Office.mdimporter
ParallelsMD.mdimporter
iBooksAuthor.mdimporter
iWork.mdimporter
/Library/StartupItems:
/etc/mach_init.d:
/etc/mach_init_per_login_session.d:
/etc/mach_init_per_user.d:
Library/Address Book Plug-Ins:
SkypeABDialer.bundle
SkypeABSMS.bundle
Library/Fonts:
Library/Input Methods:
.localized
Library/Internet Plug-Ins:
Picasa.plugin
Library/Keyboard Layouts:
Library/LaunchAgents:
com.adobe.AAM.Updater-1.0.plist
com.akamai.client.plist
com.google.keystone.agent.plist
com.macpaw.CleanMyMac.helperTool.plist
com.macpaw.CleanMyMac.trashSizeWatcher.plist
com.macpaw.CleanMyMac.volumeWatcher.plist
com.macupdate.desktop5.scanner.plist
uk.co.markallan.clamxav.clamscan.plist
uk.co.markallan.clamxav.freshclam.plist
ws.agile.1PasswordAgent.plist
Library/PreferencePanes:
Library/QuickTime:
AC3MovieImport.component
Perian.component
Library/ScriptingAdditions:
Library/Services:
WinzipAdd.workflow
WinzipEmail.workflow
WinzipUnzip.workflow
15 02 * * 1,2,3,4,5,6,7 /usr/local/clamXav/bin/RunFreshclam --quiet --log=/usr/local/clamXav/share/clamav/freshclam.log
15 03 * * 1,2,3,4,5 /usr/local/clamXav/bin/clamscan -r --log=/Users/abc/Library/Logs/clamXav-scan.log --scan-mail=yes "/Users/abc/Documents/Vuze Downloads"