Can't find ac500 with ip config tool in automation builder
IMHO, if in another pc the ip config works fine, you must search the solution inside your configuration pc's. Try to compare the configuration and change the IP number of pc that not functioning.
Do you have web server inside your PLC? Have you tried to call, for example, the web_visu page from browser with another computer? (In this case, pay attention to the version of Java that you use).
If the browser show correctly the web_visu page, the PLC do not have problem's about the ethernet connection and the problem it must be sought in the computer.
Hope this help you