How to enable NTLM for all intranet sites in Firefox?

Solution 1:

You don't have to put specific URLs in the list — you can put entire domains. So, for example, adding mycompany.com should enable NTLM for mail.mycompany.com, monitor.mycompany.com, intranet.mycompany.com, &c. (You might need to do .mycompany.com with a leading dot, actually, i can't remember — and my current job doesn't use NTLM, so i can't test.)

You can also tell Firefox to enable NTLM for any site that doesn't have an FQDN (fully qualified domain name); this is useful if your company just uses http://intranet or something similar. To enable this, set network.automatic-ntlm-auth.allow-non-fqdn to true.