Microsoft ISA Server Control failed. The failure occurred during Reading Bandwidth Control Service configuration because the system call TcModifyFlow failed. Use the source location 202.487.3.0.1200.50 to report the failure. The error code in the Data area of the event properties indicates the cause of the failure. For more information about this event, see ISA Server Help. What is this meaning? Has anyone seen before? It is just this way: First you set an effective bandwidth in KBs and then you watch the performance monitor counters as it goes in its way. Noting's wrong right then. After a while (don't know the exact time) bandwidth parameters is divided by ten at the performance counters and if you test the connection speed it is really changed. This happens for 2 weeks. You set 1000KB and it is 100KB in the next morning and everyone asks why the WAN links are too slow. And when I try to correct the mistake I get the above error about not to modify TCModifyFlow. If you don't restart nothing changes. I am searching for KB for 2 weeks and looking for something new but a huge ZERO. I hope someone is familiar with this and someone gives an advice even if these kinds of BANDWIDTH TOPICs are not popular around here.