Today i started getting a problem,,, every ip i choose to configure it returns IP CONFLICT WITH ANOTHER SYSTEM....think might be virus or hacker since all ips are not assigned.
Na i had this same trouble , it seemd to be a trojan.
I broke the networks into small segments using vlan and that solved the problem for me.
If you would check and see the conflicting mac address will be of your own pc and not some1 else.
Another problem that arises is it starts clogging the gateway resulting in the network going down.
This is probably hardware error , I have same problems when i connect one planet WAP wireles AP into my network , just try to unplug all devices one by one and you will find which one is broken ...
maybe is a arp attack, can be caused from virus or trojan or spoofing tool (man in the middle attack),
try to check your arp list cache in your RouterOS ( IP > ARP ) or Windows ( cmd > arp -a ),
if many ip addresses had the same mac address then that machine who realy had that mac address is the one caused problem,
The fix is to go to ip addresses and add a large subnet like 10.0.0.0/8 and then if you change your IP to anythign in there you won't get the conflict.