Dear My Freinds
I have a critical problem in ISA Server. The problem is the proxy settings that is assigned to the users to access the internet is removed from all the users suddenly . When I check the ISA Server I found the following error in Event log :-

The ISA Server Services cannot create a packet filter 98.131.156.99 .This event occurs when there is a conflict between the local address table (LAT) configuration and the windows 2000 routing table . Check the routing table and the LAT to find the source of the conflict .

This error occurs every 2 or 3 minutes but with different IP addresses .
Kindly advice and help me how to solve