C# dropped UDP packets on newly created socket -

hey all. i'm having issue c# , quite possibly may debugger i'm new c# (not new c/c++)

there's code below. here issue i'm having.

i udp, not guaranteed delivery, sure. expect occasional packet dropped on network or windows if i'm stuffing pipe full. however, problem having after create new socket, try , send packet 1 byte of data. packet dropped. can try , send twice, it's dropped both times. however, if send 1k worth of data, goes through. if create socket (by clicking button again), works fine. here's weird thing. if stop , restart debugging project without making changes source, packets sent without problems. seems happen on first run after project built. anyway, here's code reproduce issue. after few hours of searching , reading i'm @ loss. edit: wanted clarify i'm using wireshark , can see packets dropped.

    private void button1_click(object sender, eventargs e)     {         byte[] = new byte[1] {0x00};         byte[] b = new byte[1024];         for(int = 0; < 1024; i++)         {             b[i] = 0xff;         }          ipendpoint _ipep = new ipendpoint(ipaddress.parse("192.168.200.202"),5546);         socket _server =  new socket(addressfamily.internetwork, sockettype.dgram, protocoltype.udp);          _server.sendto(a, 1, socketflags.none, _ipep);         _server.sendto(a, 1, socketflags.none, _ipep);         _server.sendto(b, 1024, socketflags.none, _ipep);     } 

from comment arp issue, suggest ways debug , narrow down issue , suggest solutions.

how debug:

1. try making arp entry "static" pc not send arp request each time. make arp entry static can write "arp" on command prompt see list of options , add static arp entry.

2. another idea open command prompt , write "ping 192.168.200.202 -t", pc keeps on pinging other client. keep pc's arp entry date , when run c# program, not send arp again, , directly send udp.

the above points debug , ensure guessed problem right.

the possible solutions:

1. if arp issue, sure problem network switch, try replacing "switch" (i think faulty).
2. if possible can think of making "arp entry" static. might not idea situations , totally depend if nature of application allows go approach.

i hope helps.