My Book Essential 2Tb working on usb2 but not on usb3

I have purchased a My Book Essential 2Tb. it is working nicely on usb 2 ports on my Mac Pro 2006, but whenever I connect it to my allegro usb3 PCIe card, it appears mounted for a few sec, then freezes and get ejected after a while. The card is working properly with other external USB3 HD. I have installed all available drivers and softwares from WD download area.

Thank you for your kind help …

Here is the list of supported cards

http://wdc.custhelp.com/app/answers/detail/a_id/3886/session/L3RpbWUvMTM1MDY3NTI1MC9zaWQveE5EZEk3OWw%3D

try updating the firmware on the drive and the drivers for the controller in the manufacturers webpage

Thank you for your kind reply. Drivers etc. are updated. PCIe card does not appear on “not supported” cards list, but: HD is visible in disk utility, but gets not mounted at all now. I have a samsung USB3 external HD wich is working nicely with the card. Should I conclude this WD HD is not working with allegro USB 3 PCIe?

Thank you

This is what it looks like

you can try testing with another USB 3.0 controller

I have a very similar problem using the Allegro PCI3 USB 3 card on my MacPro and a My Book Essential 3Tb USB3 drive, using SL. Just wondering if you came up with a solution? I have contacted Sonnettech.com support, but they are on holidays until January 2. Thanks in advance for replying!