This a Windows issue this post explains what to do http://community.wdc.com/t5/Other-Externals/Problems-with-having-more-than-one-USB-2-0-WD-2-TB-Elements/td-p/285724
Joe
This a Windows issue this post explains what to do http://community.wdc.com/t5/Other-Externals/Problems-with-having-more-than-one-USB-2-0-WD-2-TB-Elements/td-p/285724
Joe