ln command not found causing Silverlight installation failure

Triple-click anywhere in the line below to select it:

codesign -vv /bin/ln | open -f -a TextEdit

Copy the selected text to the Clipboard (command-C).

Launch the Terminal application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.

Paste into the Terminal window (command-V).

A TextEdit window will open with the output of the command. Post the contents of that window (not the Terminal window), if any — the text, please, not a screenshot. The title of the window doesn't matter, and you don't need to post that.

You have a corrupt OS installation.

Back up all data.

Boot into Recovery mode. 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.

If you installed the Java runtime distributed by Apple and still need it, you'll have to reinstall it.