We have our 1200SWG box up and running and it's working well here.
I'm just trying to increase Availibility of our LDAP/NTLM authentication between our DCs and Smoothwall.
I have added in our extra DC's and mapped the groups across all 3 DCs correctly.
However, if I say need to reboot one of the DCs due to Windows Updates, I always get NTLM authentication pop ups on my Windows 7 clients, which then don't work correctly anyway. A reboot of the 1200SWG sorts everything, it's just a bit trivial.

Any solutions out there? Am I missing a trick?

Kind regards