To reinstall the CBOX Theme, since you’re using it for your child theme, I would recommend switching to another theme for now like Twenty Twelve.
Next:
* Navigate to your /wp-content/themes/ directory and either remove or rename the ‘cbox-theme’ directory
* Go to the WP admin dashboard and navigate to the “Commons In A Box” dashboard page
* Under the “Theme” section, you should see a link to install the CBOX Theme. Click on it and it will start downloading and installing the theme.
* The CBOX Theme should now be activated.
Now, go to the CBOX Theme Options page and see if you still run into any errors.
If you don’t, activate your CBOX child theme and that should be it.
If you still run into problems, did you recently install any plugins that might conflict with the admin area?