odpoved z Verbatimu: (ruky prec ved ono to musi fungovat, urcite mam v kazdom USB porte nieco pripojene a ten, ktory vyuziva HDD nestiha a samozrejme, ziadny iny ovladac)

Its normal that the copy speed changes because it is dependent on how many files and how many data at all is copied.
Dependent on the sizes of the files the speed can go down. Important that it continues until the end, even its slow.
Does it not copy and stop with an error or what ?

That is a 2TB mobile hard drive, which needs much power from the USB ports. ON a desktop PC connect it to the back panel USB3.0 ports please.

You should connect it to a USB3.0 port at least and remove other external storage devices. Having too many USB devices can end

up with too less power for some devices. Remove also external USB hubs and docking stations.

This product works by plug and play with windows drivers. There are no alternative drivers for that.