Hi I hope someone can help I got my son a new computer for Christmas which has windows 8.1 seem to be having a lot of trouble opening files that I have downloaded
, these sites are on his laptop which was windows 7 and I didn't have any problems with, I am downloading esf 123 version which runs with Half-Life (on steam) and when I try to open it is says cannot verify publisher and it then asks me where I want to open it , i.e. internet explorer, note book etc it won't let me open it at all keeps saying cannot verify publisher, my son uses this site on his laptop with no problem how do I open this file, please help its driving me mad, ps be gentle i have no experience with computers but can follow plain instructions. Thank you