2 my passports not working at the same time

I’ve been experiencing difficulties to get both of my new 1TB My Passports to work at the same time. Both work when plugged in by themselves but when I plug both in, my laptop will only read one and the other doesn’t seem to appear.

Would anyone be able to help me to get both of them working at the same time?

This is a Windows problem this post explains the fix http://community.wdc.com/t5/Other-Externals/Problems-with-having-more-than-one-USB-2-0-WD-2-TB-Elements/td-p/285724