I have a few ideas, each is separated by a line. Hopefully one of these will work for you.
Since a ping returns, I would suspect you need to type that IP into your browser to access the NAS home page.
From here, you should be able to login and set permissions.
Downgrade to an earlier version, like 4.2.21
For your Readynas and Windows 8 issues see this link
Try to connect by IP and by name (IE, in explorer, type in \NameOfNas or \NameOfNas\Public or \192.168.1.X or \192.168.1.x\Public)
Open up your routers home page and see if both devices are connected (many routers give a graphic image or textual detail what is connected via DHCP).
See if you can access the device from another machine to see where the fault is (it could be with the NAS). If another device can access the device, see if you change permissions for your machine.
It could be the antivirus or anti'ware, so disable all protection and see if the issue persits.
Create a shared folder on another machine and see if your computer can access it to indicate/help prove if the issue is with your machine or not.
You can also try the following command in cmd prompt
net config server /autodisconnect:-1
Others have reported the following registry editor hacks work (only do
this if you know what you're doing)
Apparently you need to tell Windows that you want to use the machine
as a file server and that it should allocate resources accordingly.
Set the following registry key to ‘1′:
After that navigate too the following key:
and set this registry key to ‘3′:
There is a setting in windows Local Security Policy which is
incorrectly set by default for viewing an older communication protocol
To access said setting go to the control panel in Windows 7, in
Category view click on the text "System and Security", then click on
the text "Administrative Tools".
Now double click and open "Local Security Policy".
In the Local Security Policy screen on the left navigation tree,
expand the "Local Policies --> Security Options" then about 2/3rd's
the way down the list you'll see a Policy called "Network Security:
LAN Manager authentication level". Double click and change the
setting to be "Send LM & NTLM - use NTLMv2 session security if
Then just press OK and close all of the open windows and then try
Type in the IP into explorer without the leading
Use the software it came with (if any) to see if it can automatically detect it for you.