W2k/Proxy – No Domain Server Available

Have a W2k server with MS Proxy 2.0 Installed. Had w2k sp 1 installed. Recently installed ms01-037 security update. After install reboot of server was required. After reboot this server will not find any domain server on our network. We have NT 4 PDC and 2 BDC’s all with sp6a. All other machines see the PDC & BDC fine. Can ping from the Proxy machine to PDC & BDC by ip and name. If I recall correctly error log show #5719. This machine had be up and running for 72 days prior to this with no problems. Have already tried uninstalling hot fix and have installed W2k sp2. Any Ideas ? Thanks jeff