You tell us nothing about what the application is or what it does and what IP addresses you are actually using. We need more information to help you.
Tell us what the application is,
what exactly is it doing when the crash occurs?,
what crashes, the application or the whole network?
what IP addresses are being used on your network? (there will be a tool to find this in your OS or router configuration)
Frequently, problems like this can be traced to duplicate IP addresses being used or there being two DHCP servers on the same network but we can't see your configuration so you will have to tell us what it is.
Brian.