Web browsing with Firefox needs addtional setup in order to work. This is due to the nature of what it supports by default. Here are the instructions to resolve any authentication issues.
1. Click Start, Programs, Mozilla Firefox, Mozilla Firefox.
2. Type about:config in the address bar and, if prompted, confirm your intention to make the modifications.
3. In the filter field enter network.negotiate-auth and press ENTER.
4. Navigate to the entries named network.negotiate-auth.trusted-uris and network.negotiate-auth.delegation-uris.
5. Double-click network.negotiate-auth.trusted-uris and add the FQDN (Fully Qualified Domain Name) of the appliance using the syntax below:
6. Click OK. The values below should be displayed for the various columns of network.negotiate-auth.trusted-uris:
Status = user set,
Type = string
Value = <local-FQDN>.gvsd.ca
7. Double-click network.negotiate-auth.delegation-uris and add the FQDN.
8. Restart Firefox.
Please note that this is unsupported, and done at your own risk.