You'll have to ask him to turn off his Xbonz blocking filter... Some people!
Seriously though, if you're on Win 7,8,10 your security and or firewall settings are blocking 3rd party linking without appropriate certificates. If his picts are off .org sites (notorious for out dated certs.) You may need to loosen your security pucker factor. You might also check your IE or Edge blocked sites list, sometimes it sucks up a site address and won't let go.
Kind of like a rabid
bite...