There are a lot of forums where people are having trouble writing to the WD ShareSpace and getting an Access is Denied error. I have seen this plenty of times, and no matter if you set the shares to Public access, or set users with permissions, it is the same thing. While i think the root problem lies with Western Digital’s architecture, there is a way around it that works well.
First, create the share you want to use, or use an existing share you have already setup and are having trouble with. After that, set the user permissions in the web interface to be Public, or whatever you would like. So far, this is probably what you have done with no luck writing to the Network Attached Storage (NAS) device.
This is the part that will help you. Browse to the device in Windows Explorer (\[NAS Name or IP Address]), and right-click on the share you are trying to use. Go to the security tab and click advanced. Go to the Owners tab and make yourself the owner; you will probably see the current owner is “root(Unix Userroot)”. You will want to put a check mark in the “Replace owner on subcontainers and objects” also, so this change trickles down if you have any other folders there. Click OK until you are back at the Windows Explorer view.
You should now be able to write and delete to the share. To be sure you are the owner, you can always right click in the column header and add Owner to the current view to confirm you are now the owner.
I hope this helps get your Western Digital ShareSpace NAS online and usable for you.