i'm network admin in a manufacturing unit i have a bad experiance with ISA on Exchange before i was runing Exchange 5.5 with proxy (winnt)on a 56kbps line Then we decide to upgrade to win2k environment so we hsd decied to run ISA and Exchange2000 in Win2000 Server on a single server. so then we run it successfully but after some hours i watch that E-mails are not recieving because badwidth was excelerated by ISA and there was no room for Exchange Now we are running ISA and Exchane on Different Servers.