Ack number always equals 1

[Giox79]

Good morning everyone,
I'm a newbye in networking application and I trying to debug a strange problem that I have sending through TCP protocol some data from an embedded system to a PC application
The problem is that that the application running on PC disconnects after few packets, and so I used wireshark to debug the problem.
It seems some packet get lost (I use a cross cable to connect the devices) and that the system isn't able to recover from such a problem.
Furthermore I found out that the acknowledgement number generated by the server application always equals 1.
Do you have any idea about some wrong setting that could generate such a behaviour?
Giovanni

[attac]

hm... interesting