If you are using shared web hosting from companies like GreenGeeks for your Drupal website, you should configure a cron job to run Cron.php via Cpanel. Cron.php is the file that Drupal uses to for general maintenance tasks, such as indexing your site for the site search, and cleaning up log files.

Step 1:
Login to your CPanel and scroll down to the Advanced section. Click on the "Cron Jobs" icon.

Step 2:
Populate the "Add New Cron Job" section like the example below. For a small site, you might set up this cron job to run once a day. For a more active site you might want to run that job more often—perhaps every few hours or every hour.

That's it. You should be good to go.