I'm working in the IT department for a South African University. We run ISA 2004 Enterprise. When users open a browser on campus they prompted to login with their ISA credentials, usernames@wf and their passwords.
In IE, they do this and they are authenticated until they close their browser. In Firefox however, they need to do this multiple times (enter username and password up to 10 times), the ISA login box just keeps appearing for no reason. Ticking 'remember password' has no affect.
What we now do is store our credentials using XP's account/password manager. So when opening IE now, it doesn't prompt for ISA login as it pulls these credentials from the one's we've saved in XP.
Firefox also opens (often) without asking for an ISA login. Then, for no reason, you can be browsing pages and all of a sudden it prompts for an ISA login. You have to enter them multiple times before the box goes away.
A work around we've found, to lessen the amount of times/frequency that the ISA login appears in Firefox, was to change network.automatic-ntlm-auth.allow-proxies;false (from true to false)
That was the case with Firefox....until we tried Firefox 3. Now, this problem seems even greater.