BleepingComputer.com: NAS Connection issue

I have a small NAS setup and every wireless device I have can happily connect to it except my own pc.
The NAS is connected to a Netgear wireless router by cable as is my pc.
I can ping it and bring up its config page in a browser, I'm running Windows 7 and set as administrator.
If I look at my network in an explorer page the device is shown, but when I double click it, a windows dialogue pops up with the following:
"\\xxxxx-xxxx is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions"
If I type \\xxxxx-xxxx\public into an explorer window I get the following network error;
"Windows cannot access \\xxxxx-xxxx\public. Check the spelling of the name. Otherwise, there might be a problem with your network. To try and reslove network problems ,click diagnose" Diagnose finds no solutions.
I also have a second pc running Windows 7, set up exactly the same and it can connect to it, the only difference being it is wireless.
I've tried switching off the Windows firewall but that made no difference.
Any ideas?

Are you using the IP address or the name of the NAS in the browser?

There has to be something different between the 2 PCs besides one being wireless. Just to test, is it a wireless laptop with wireless built in? If yes bring it to where the other PC is and connect it wired to see. If its a desktop with a USB wireless dongle move it to the other PC, install it and see if you can connect.

What firewall is on both?