I just upgraded to 10.7.3 and now I can't install any applications.

Question

I just upgraded to 10.7.3 and now I can't install any applications. Everything else in the OS and in applications seems to work OK. After the installers ask for the system password, they do nothing. I doesn't hang; it just won't proceed any further in the install process. I can press the back button and it seems to do that just fine. I repaired the disk permissions, but to no avail.
After I installed 10.7.3, I tried to install an updater that was listed as being recommended for Time Machine users. That was the first time I tried to launch an installer of any sort and it did the same as above. I've gathered since then that the update wasn't necessary and was already included in the 10.7.3 I loaded today.
Any hints?

Answer 1

I'm having a similar problem after installing 10.7.3 and the Messages beta. I've unistalled Mesages with little bit of trouble.. Linc, I followed the step given in your final post any help would be appreciated.
A screenshot of my actual error. I get this error not just for Flash, but also Handbrake. I receieve th error even when I try using a programs automatic update. However, not suprisingly I do not get the message when using Apple's software update.
Step 1 results
com.symantec.kext.internetSecurity (1.3.2f5)
com.symantec.kext.ips (3.2f8)
com.cisco.nke.ipsec (2.0.1)
com.symantec.kext.SymAPComm (11.1.2f17)
Step 2 results
org.macosforge.xquartz.privileged_startx
com.symantec.symSchedDaemon.plist
com.symantec.symdaemon
com.symantec.sharedsettings
com.symantec.Sched501-2.plist
com.symantec.Sched501-1.plist
com.symantec.navapdaemonsl
com.symantec.navapd
com.symantec.MissedTasks.plist
com.symantec.diskMountNotify.plist
com.symantec.avscandaemon
com.micromat.TechToolProDaemon
com.google.keystone.daemon
com.bombich.ccc
Step 3 result
org.macosforge.xquartz.startx
com.symantec.uiagent.application
com.prosofteng.DGMonitor
com.micromat.TechToolProAgent
com.google.keystone.root.agent
com.google.Chrome.framework.service_process/Users/damian/Library/Application_Sup port/Google/Chrome
com.ecamm.printopia
com.adobe.ARM.df0ab5bbe6f698196fcc21e3c1e66dcb758bd911f4d637272d9d8109
Step 4 result
/Library/Components:
/Library/Extensions:
/Library/Frameworks:
AEProfiling.framework
AERegistration.framework
Adobe AIR.framework
AudioMixEngine.framework
Frameworks
NyxAudioAnalysis.framework
PluginManager.framework
R.framework
TSLicense.framework
cisco-vpnclient.framework
iLifeFaceRecognition.framework
iLifeKit.framework
iLifePageLayout.framework
iLifeSQLAccess.framework
iLifeSlideshow.framework
/Library/Input Methods:
/Library/Internet Plug-Ins:
.DS_Store
Flash Player.plugin
Flip4Mac WMV Plugin.plugin
Google Earth Web Plug-in.plugin
JavaAppletPlugin.plugin
OfficeLiveBrowserPlugin.plugin
Quartz Composer.webplugin
QuickTime Plugin.plugin
RealPlayer Plugin.plugin
Silverlight.plugin
Unity Web Player.plugin
Unused
flashplayer.xpt
googletalkbrowserplugin.plugin
iPhotoPhotocast.plugin
npgtpo3dautoplugin.plugin
nsIQTScriptablePlugin.xpt
/Library/Keyboard Layouts:
/Library/LaunchAgents:
com.google.keystone.agent.plist
com.micromat.TechToolProAgent.plist
com.prosofteng.DGMonitor.plist
com.symantec.uiagent.application.plist
org.macosforge.xquartz.startx.plist
/Library/LaunchDaemons:
com.apple.remotepairtool.plist
com.bombich.ccc.plist
com.google.keystone.daemon.plist
com.micromat.TechToolProDaemon.plist
com.symantec.MissedTasks.plist
com.symantec.Sched501-1.plist
com.symantec.Sched501-2.plist
com.symantec.avscandaemon.plist
com.symantec.diskMountNotify.plist
com.symantec.navapd.plist
com.symantec.navapdaemonsl.plist
com.symantec.sharedsettings.plist
com.symantec.symSchedDaemon.plist
com.symantec.symdaemon.plist
org.macosforge.xquartz.privileged_startx.plist
/Library/PreferencePanes:
Flash Player.prefPane
Flip4Mac WMV.prefPane
SymantecQuickMenu.prefPane
TechTool Protection.prefPane
/Library/PrivateFrameworks:
SymAVScan.framework
SymAppKitAdditions.framework
SymBase.framework
SymDaemon.framework
SymIPS.framework
SymIR.framework
SymInternetSecurity.framework
SymScheduler.framework
SymSharedSettings.framework
SymSubmission.framework
SymUIAgent.framework
SymUIAgentUI.framework
/Library/PrivilegedHelperTools:
com.bombich.ccc
/Library/QuickLook:
GBQLGenerator.qlgenerator
iWork.qlgenerator
/Library/QuickTime:
AppleIntermediateCodec.component
AppleMPEG2Codec.component
Flip4Mac WMV Advanced.component
Flip4Mac WMV Export.component
Flip4Mac WMV Import.component
Google Camera Adapter 0.component
Google Camera Adapter 1.component
/Library/ScriptingAdditions:
/Library/Spotlight:
GBSpotlightImporter.mdimporter
LogicPro.mdimporter
Microsoft Office.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:
Google Earth Web Plug-in.plugin
WebEx.plugin
fbplugin_1_0_3.plugin
Library/Keyboard Layouts:
Library/LaunchAgents:
com.adobe.ARM.df0ab5bbe6f698196fcc21e3c1e66dcb758bd911f4d637272d9d8109.plist
com.apple.AddressBook.ScheduledSync.PHXCardDAVSource.E9E876AD-F4B4-43BE-A4F2-EC7 33492E799.plist
com.ecamm.printopia.plist
com.google.Chrome.framework.plist
Library/PreferencePanes:
Printopia.prefPane
Step 5 result
AdobeResourceSynchronizer, iTunesHelper, Air Video Server