Hi,
I recently managed to get a network share from my PC set up on my Pi:
My share is on an external hard drive attached to my PC - E:/RetroPieShare - inside this I copied 4 folders from my pi (home/pi/RetroPie - this will copy all the files on your SD card to the external hard drive on your PC :
0_1486470761915_1.png
I then edited the fstab file:
0_1486471142739_3.png
like this:
0_1486471548395_4.png
The next bit was key: the path to the share on the external hard drive in fstab must match the properties shown in windows highlighted in blue - (remember to change the \ to / in the fstab file):
0_1486471667567_5.png
(Also remember to share this folder)
I can now add roms into the roms folder on the external hard drive & they appear in the home/pi/Retropie/roms folder which should appear in Emulation Station