Permissions window has no text, does not respond

Question

Whenever the permissions window pops up to verify my username and password, there is no text on it and (when I type in my username anyway) it will not accept the text, so nothing happens. I have gone through SYSTEM PREFERENCES to see if something looks odd, but when I try to unlock SECURITY + PRIVACY settings, of course, the permissions window pops up -- with no text.
How do I repair this? Do I have to re-install the OS?

Answer 1

Launch the Console 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 Console in the icon grid.
The title of the Console window should be All Messages. If it isn't, select
          SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
          View ▹ Show Log List
from the menu bar at the top of the screen.Click the Clear Display icon in the toolbar. Then try the action that you're having trouble with again. Select any messages that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
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