Safari for Lion no longer works (backslash through the Application). I have tried to reload but that will not work because it says I have a higher version already installed. I tried to eliminate the current non working Safari but it is not allowed as "it is reqd for OS 10.7. How can I reinstall a working version of Safari.
Boot into Recovery by holding down the key combination command-R at the startup chime. Release the keys when you see a gray screen with a spinning dial.
Note: You need an always-on Ethernet or Wi-Fi connection to the Internet to use Recovery. It won’t work with USB or PPPoE modems, or with proxy servers, or with networks that require a certificate for authentication.
When the OS X Utilities screen appears, follow the prompts to reinstall the OS. You don't need to erase the boot 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, so make a note of those before you begin.