vb.net - Hot to use more socket? -

i have form called frmmsg. following warning when open new frmmsg :

only 1 usage of each socket address (protocol/network address/port) permitted.

how can open form using more socket?

this code i'm using:

imports system.io imports system.threading imports system.net.sockets public class frmmsg     dim listener new tcplistener(8000)     dim client tcpclient     dim message string      private sub frmmsg_load(sender object, e eventargs) handles mybase.load         dim thread new thread(new threadstart(addressof listening))         listener.start()     end sub      private sub listening()         listener.start()     end sub      private sub btnnewform_click(sender object, e eventargs) handles btnnewform.click         dim fnew new frmmsg         fnew.show()     end sub end class 

where problem , how can solve it?

as apparent message can open 1 listening socket per port (in general).

therefore, must ensure there 1 instance of tcplistener(8000) @ same time. if want have multiple forms open @ same time need reference object not form instances. maybe use static/shared variable.