Problem while rooting : <OSM> All threads completed. (succeed 0 / failed 0)

I was trying to root my SM-G920F ,which is running Android 6.0.1, when i received the following message on Odin3. Enter CS for MD5.. Check MD5.. Do not unplug the cable.. Please wait.. CF-Auto-Root-zeroflte-zerofltexx-smg920f.tar.md5 is valid. Checking MD5 finished Sucessfully.. Leave CS.. All threads completed. (succeed 0 / failed 0) the phone was in download mode (Odin) and the developer option is On as it is the case with USB debugging, also the reactivation lock is off. > Android version : 6.0.1 >Baseband version : G920FXXU4DPI9 >Kernel Version : 3.10.61-8821257 Sep 16 2016 >Build Number MMB29K.G920FXXU4DPIL >KNOX Version : KNOX 2.6 ANY help will be appreciated.