Samsung G610F Flashing Issues

Z3X
Operation: Flash
Selected model: SM-G610F
Software version: 31.0

File analysis... OK
Total file size: 0xEF433DD0 (3828 Mb)
Searching USB Flash interface... COM21 detected
Setup connection... error

Done with Samsung Tool PRO v.31.0

Tried With All Other Tools.
Same Result.:confused: