Hello Clement! (Be careful in what you post to the Internet, your name is in the screenshot, just sayin' If you want to be able to blur things in screenshots before posting them, try Skitch, it's a free app on the Mac App Store)
In the past, I've seen this being caused by ISP's DNS servers.
Try the following:
- Unplug your modem from the power, wait a minute, and plug it back in. If your issue is solved now, celebrate š
- If not solved, however, try and see if you have the same issue on another network.
- You can also change the DNS server you use to something like OpenDNS. There is a guide here, preferably set it up on your router, but if that's too technical, try setting it up on your Mac only: https://store.opendns.com/setup/?__utma=247635969.764677354.1418757510.141875751 0.1418757510.1&__utmb=247635969.3.10.1418757510&__utmc=247635969&__utmx=-&__utmz =247635969.1418757510.1.1.utmcsr=google|utmccn=%28organic%29|utmcmd=organic|utmc tr=%28not%20provided%29&__utmv=-&__utmk=7372593#/
One last thing about changing DNS servers. Really, your internet provider should be more than capable of serving you pictures from Amazon and Facebook (by the way, most of these pics are not hosted by Amazon and Facebook really, but by an outside company called Akamai that a lot of large companies use. So I should probably be saying: "your ISP should not have any trouble serving content from Akamai's servers")
Hence, the proper advise I should give you is: contact your ISP and ask them if they've been having DNS issues lately. Barring that: you can save yourself some helpdesk pain and use OpenDNS or Google DNS.