users cannot log on to FTP site

Dear all
I am using an FTP server on window NT4 SP6a domain controller, every thing was working fine, but all of the sudden all of the users cannot access the FTP site from outside the company (but can access it from local LAN), the site keeps asking for the username and password although they are given to it every time, i did all the instructions on http://support.microsoft.com/?id=200475 but nothing worked out, there is no thing strange in the event log

any suggestions please

thanks alot

Laith

On Wed, 29 Oct 2003 09:56:11 -0800, Laith Hattab
<anonymous RemoveThis @discussions.microsoft.com> wrote:

 >I am using an FTP server on window NT4 SP6a domain controller, every thing was working fine, but all of the sudden all of the users cannot access the FTP site from outside the company (but can access it from local LAN), the site keeps asking for the username and password although they are given to it every time, i did all the instructions on <a style='text-decoration: underline;' href="http://support.microsoft.com/?id=200475" target="_blank">http://support.microsoft.com/?id=200475</a> but nothing worked out, there is no thing strange in the event log

Proxy, firewall?

Jeff<!-- ~MESSAGE_AFTER~ -->