In my organization, we have two ISA servers configured to work in an array. They were configured to allow Internet access from 172.x.x.x series.
We had the requirement to allow the Internet from 192.168.x.x series as well. I modified the rule to allow for the same. But in case of 192.168.x.x series always the Default Enterprise rule was being fired and the request was being denied.
We had to reinstall the ISA in order to make it work. The same rule started working fine after re-installation.
What could be the reason?