Apple Mail with OSX 10.9.5 quits on launch when mail window opens. May be related to install of Security update 2014-005. Any suggestions on fixing this?

Question

Apple Mail with OSX 10.9.5 quits on launch when mail window opens. May be related to install of Security update 2014-005. Any suggestions on fixing this?
Here is the beginning of the  Problem details error message:
Process:    
Mail [763]
Path:       
/Applications/Mail.app/Contents/MacOS/Mail
Identifier: 
com.apple.mail
Version:    
7.3 (1878.6)
Build Info: 
Mail-1878006000000000~1
Code Type:  
X86-64 (Native)
Parent Process:  launchd [264]
Responsible:
Mail [763]
User ID:    
501
Date/Time:  
2014-10-20 15:23:32.902 -0800
OS Version: 
Mac OS X 10.9.5 (13F34)
Report Version:  11
Anonymous UUID:  1058C7CE-141A-982C-2F1D-4F0EB47F37A1
Crashed Thread:  10  Dispatch queue: NSOperationQueue Serial Queue
Exception Type:  EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Application Specific Information:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSKeyPathExpression objectForKey:]: unrecognized selector sent to instance 0x60000045ff20'
abort() called
terminating with uncaught exception of type NSException

Answer 1

Try a restart.
Do a backup, using either Time Machine or a cloning program, to ensure files/data can be recovered. Two backups are better than one.
Try setting up another admin user account to see if the same problem continues. If Back-to-My Mac is selected in System Preferences, the Guest account will not work. The intent is to see if it is specific to one account or a system wide problem. This account can be deleted later.
Isolating an issue by using another user account
Try booting into the Safe Mode using your normal account.  Disconnect all peripherals except those needed for the test. Shut down the computer and then power it back up after waiting 10 seconds. Immediately after hearing the startup chime, hold down the shift key and continue to hold it until the gray Apple icon and a progress bar appear and again when you log in. The boot up is significantly slower than normal. This will reset some caches, forces a directory check, and disables all startup and login items, among other things. When you reboot normally, the initial reboot may be slower than normal. If the system operates normally, there may be 3rd party applications which are causing a problem. Try deleting/disabling the third party applications after a restart by using the application un-installer. For each disable/delete, you will need to restart if you don’t do them all at once.
Safe Mode - Mavericks
Safe Mode - About