OK, first at all, you need to find out what IP’s are used on the routers of that LAN. You could use some tracing tools like the Advanced IP Scanner which you could download free from: http://www.advanced-ip-scanner.com/

You have to key in the IP Range of the LAN system like 192.168.1.1 to 192.168.1.254. This you could find (if you didn’t know already) using in Windows Command Prompt (CMD) or PowerShell the command: ipconfig /all

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