Tallest Skil, thanks for responding so fast and for the advice. I am pretty careful with opening/downloading files. After I posted my message here, I ran an app called Adware Medic. It found a few supposed adware files, so I deleted them and rebooted my Mac. I haven't deleted Flash yet because it's used by a few sites I frequent. But I will consider uninstalling it. Thanks again!
8/1/15 at 10:36pm