Can't open the application Safari... not supported on this type of MAC

Question

Installed Software:
9/20/13 10:15 PM     Digital Camera RAW Compatibility Update     4.09
9/20/13 10:15 PM     Security Update 2013-004                             1.0
9/20/13 10:15 PM     iTunes                                                         11.1.0
8/18/13 12:25 AM     Security Update 2013-003                              1.0
6/22/13  1:30 PM     Safari                                                            6.0.5
6/22/13  1:30 PM     Security Update 2013-002                               1.0
3/4/13 8:41 PM        MacBook Pro SMC Firmware Update               1.7
3/4/13 8:41 PM         Safari                                                           6.0.2
2/13/13 2:18 AM     Mac OS X Update                                            10.7.5
Since the 9/20/13 update, I see a circle with a line through it on top of the Safari application. When I try to execute anyway, I get:
   "You can't open the application Safari because it is not supported on this type of Mac."
I vaguely remember some capability to rollback any updates. Is this true?
Where should I go from here?

Answer 1

First you need to clear out some space on the startup volume. You should have at least 9 GB available. Then do as follows.
If you don't already have a current backup, back up all data, then reinstall the OS. You don't need to erase the startup volume, and you won't need your backup unless something goes wrong. If your Mac was upgraded from an older version of OS X, you’ll need the Apple ID and password you used to upgrade.
If you installed the Java runtime distributed by Apple and still need it, you'll have to reinstall it.