I am using a mid-2009 Macbook Pro with OS X 10.11, El Capitan.
Yesterday, my computer stopped allowing me to access http websites. I can access only https websites. This problem affects all browsers I have (Safari, Chrome, and Firefox). I tried resetting my modem and router (airport express) and my computer. My wife also has a Macbook and she is having no issues so it is something with my computer. I have searched for an answer and found others who have had the same issues but non of their fixes worked for me.
I also have the following third party software: Thursby pKard for Mac and Eset anti-virus. I tried completely disabling the anti-virus and that did not fix the issue either.
Any help would be greatly appreciated.

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