Java not receiving udp packets on windows 7 -

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i'm making system reading smart-cards. reader devices send out udp packets. wireshark can see packets says have incorrect frame check sequence. on windows 7, while on debian works flawlessly. tried adding rules, specific ports used, firewall... disabled altogether... no joy :/

i wrote bare bones code should verify packets reaching java app : 

try {     datagramsocket s = new datagramsocket(null);     inetsocketaddress address = new inetsocketaddress("192.168.1.100",8888);     s.bind(address);     byte buffer[] = new byte[1024];     datagrampacket packet = new datagrampacket(buffer, buffer.length);     while(true)     {     system.out.println("waiting...");     s.receive(packet);     system.out.println("received!");     }     } catch (exception e) {     e.printstacktrace(); }

it seems aren't ... ideas?


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