Javascript suddenly stopped working
Macbook Pro w/ Retina, Mid-2014, OS X Mavericks 10.9.5, Safari 7.1.3.
Safari security settings: enable Javascript checked, allow plug-ins checked, under manage website settings, Java set to allow.
Security software: Kaspersky* (recently removed - see below)
The day before yesterday I was watching a show on Hulu. The settings were set as above, along with the security software. Everything worked fine. When I was done, I closed Safari and shut down the computer. Neither I nor anyone else turned on or used the computer in any way until today. I turned it on, logged on, and opened Safari. When I went to Hulu, however, it said that Javascript was not being allowed to run. I checked my settings, and they were (and still are) set as listed above. I removed the Kaspersky software, to see if that was the problem. It then began to load Hulu, but froze in the middle of loading. It did this also with Netflix, Crunchyroll, and Vudu. I decided to check other, non-video sites. Some of those (such as Amazon and my local library website) either never loaded or loaded very slowly with errors (no graphics, etc), while others (such as my school website) loaded just fine.
It isn't the internet connection at my location. I have tried those sites with 2 other devices: an ethernet-connected desktop Windows computer (chrome) and a wireless connection through my iPhone (safari). Both display all sites just fine. So I know it's a problem with Safari on my Macbook.
Any help would be very much appreciated.
MacBook Pro (Retina, 15-inch, Mid 2014), OS X Mavericks (10.9.4)