having same issue on my Samsung S5 G900F.....even installing custom recovery failed
<ID:0/003> Added!!
<OSM> Enter CS for MD5..
<OSM> Check MD5.. Do not unplug the cable..
<OSM> Please wait..
<OSM> G900HXXU1BOG5_G900HODD1BOG1_G900HXXU1BOG4_HOME.tar .md5 is valid.
<OSM> Checking MD5 finished...