I think you need a DLNA server or more. http://www.lg.com/uk/tvs/lg-42LN578V noted MIRACAST so look for a MIRACAST or DLNA server for your PC to make the bridge without more gear.
PS. LG needs to answer their privacy issues. Read http://bgr.com/2013/11/20/lg-smart-tv-spying/
Basically I have an eircom efiber router, which i have attached my seagate external hard drive to.
Is it now possible to have my LG TV (42LN578V) pick up this hard drive over wifi and allow me to play the files from the hard drive?
I can access this hard drive from laptop without any issues. (Had to change file sharing on router as was originally disabled)
If I connect hard drive straight into usb point on tv it picks up the hard drive automatically when i go into the SmartShare but it's not currently showing up when hard drive is connected to router.
Do I have to install something else, chnage a setting on the tv or is it just not do able on this make of tv....any help would be much appreicated.