hi again Seems to be related to the #define MEM_SIZE
I manage to make it happen with Win7 allso. I just needed to send a bigger packet.? But increasing the MEM_SIZE seems (??) to help. But why do it crash and not just make an error? Or does lwip not check if memory is availble? Thomas -- View this message in context: http://lwip.100.n7.nabble.com/Works-with-Win7-not-Windows-XP-tp22003p22005.html Sent from the lwip-users mailing list archive at Nabble.com. _______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users