Did you setup a Homegroup? Home sweet homegroup: Networking the easy way in Windows 7
If you have a Security or Firewall Software, pls. disable it for now. If you are using Windows built-in Firewall, make sure to exclude File and Printer sharing.
In addition to the link please create the same UserName and Password on both computers.
Alternatively, try accessing the shared folder or Drive this way:
Click on the Windows Orb, type \\ComputerName\SharedFolderName
press enter, also the Computer Name can be replaced by an IP Address.