Active mode FTP client programs cannot access an FTP server from behind Internet Security and Acceleration Server 2004
Troubleshooting FTP access problems leave many ISA Firewall admins bald from tearing their hair out trying to find a solution. Here’s a great KB article on a specific cause of FTP problems related to the Firewall client.
Check it out at:
http://support.microsoft.com/kb/884580/en-us
HTH,
Tom
Thomas W Shinder, M.D.
Site: www.isaserver.org
Blog: http://blogs.isaserver.org/shinder/
Book: http://tinyurl.com/3xqb7
Email: tshinder@isaserver.org
MVP — Microsoft Firewalls (ISA)
