Jiri brought to my attention that that asus provide firmware upgrade which solved his problem.
I found at https://www.asus.com/Optical-Drives-Storage/AN300_External_HDD/HelpDesk _Download/ utilities which correspond my HDD, i.e.: 1. firmware upgrade utility 2. virtual cd removal utility I succeeded to run them under windows (wine didn't helped...). And ... it worked! After the firmware upgrade the block device was generated, though the partition was not recognized. I used the second utility and removed the virtual cd and everything is getting mounted in linux! Ido
