Cannot access Private folder through lan by admin

I want to have a private folder which has access to all computers on the LAN. But should have no access through internet. First, I cannot map a private folder to any drive letter. The folder can be mapped only if it is public. This public folder can be accessed by all on LAN or through internet,. When I make this folder private, the LAN access still remains, including drive letter but Internet access is denied. This remains until I switch off & switch on my laptop. After that, the folder can be seen as network drive but cannot be accessed through LAN. The pop up window asks for username , password . But even after filling those details , access is denied.

Any solution ?

You will have to create a public folder for your LAN users, but then edit the smb-global.conf for that share to add a hosts deny = parameter for the internet IP. See smb.conf.

Apparently, the problem was with windows 7 security setting. It is now resolved.