  Out of date browsers and or Malware likely. This is not a dell support issue. Microsoft Safety Scanner is a scan tool designed to find and remove malware from Windows computers. Simply download it and run a scan to find malware and try to reverse changes made by identified threats. Download Microsoft Safety Scanner (32-bit) Download Microsoft Safety Scanner (64-bit)   [URL]  
I use 1.5 yrs old dell inspiron laptop with windows 10 operating system. All of a sudden some websites doesnt load on my laptop. I tried everything from changing dns server settings to flushing dns cache in cmd. This helped with the ones not working earlier(youtube, general google search) but for some reason the sites that worked ok before aren't  loading (slack, discord, extramarks, links). It'd  be great if someone can help me out
Certain websites not loading