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You can cross reference them here
http://support.wdc.com/knowledgebase/answer.aspx?ID=1378

And they look something like this....

I have swapped power supplies on WD externals and had that work.
I think what happened was it cleaned the connection as the original did work after that.

Unplug everything else, then try it.

Connect to the computer, not to the hub.
USB only has 500ma available and the hub and stuff maybe drawing to much.

Now a powered hub, one that plugs into a wall socket too, it has enough power....