My computer in Home network, it used few computers, (Their connected to router using Wire and WiFi)
I made project from using VB.Net and MS-Access, DataBase used from network path,
Project was working fine,

If any computer run my project out of Home Network, it show error message.

If there any way to Know SSID of My Network or If can I know this computer connected to specified(My Network) Network, then I can show msgbox like "Not in Network" and Exit,

The problem is most likely with the Firewall that's on the computer hosting the database. Change a firewall setting to open up the port your program is using. I had to do that with my own Home Network in order to get a similar program running on my computers.