Are there any other computers on the network that can see it?
What are you connecting to it with FTP, SMB, AFP?
Right, but what are you connecting to it with? If it is a NAS which it should be it would have an IP address and you would connect to it via SMB, FTP, SFTP or AFP. One on these protocols must be used.
Does anything show up under Shared in Finder?
It sounds like it is not mapped to your computer now. Western Digital suggests this article to help you remap the drive. Please follow the instructions and let me know if the issue is resolved.http://support.wdc.com/knowledgebase/answer.aspx?ID=2686
Did this work?
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