Dunno if it's just me.....I've had zero problems doing ....well....anything I want to ?!?
BTW, I used ES file explorer (file exploder?) on my Galaxy Nexus.....constant issues and crashes.
On your S5 there is a app called "My Files", it seems to work almost exactly like ES is supposed to work.
It does everything I can think of....make folders, open and add to them, delete files and folders ???
Works perfectly on mine with a 32gb Pony class 10 micro SD, not a single problem ever.
Perhaps you have a problem SD card ?
Err, it's a PNY sd card, just always seemed like calling it a Pony was the correct term ?
Samsung A680>Samsung Blade A900>Sony TM506>Samsung Vibrant T959>HTC Evo4g>HTC Evo3D>Motorola Photon>Galaxy Nexus>Galaxy S5 (couple missing from there, oh well)