Hello,  I'm with the same problem!!  In my case it was caused by a malware called RocketTab, this is installed as a proxy so you need to remover it by the Control Pannel, or as i did, delete the folder Search Extensions in Program Files.  Dell Inspiron 5447
Don't require a proxy setting....mine keep setting up w/loopback...how can I get ride of this issue? 
Proxy settings keep changing