Can win7 be added to an NT 4 latest SP domain? Getting a message "looking for AD domain controller"Thanks

No, I belive XP was the last OS to suport NT domains. Though I never tried Vista.

Vista could, although it was unsupported (because NT4 stopped being supported two years before Vista's release). Win7 cannot join an NT4 domain. Please migrate off of NT4, you have not gotten a security update there in more than 3 years.Ned Pyle [MSFT] - MS Enterprise Platforms Support - Beta Team

Hi, I have still a NT4 DC, when upgrading a WS to Win7, everything worked fine, except the login, because of 'trust relationship failed'. Then I have removed the machine account from server manager, and changed on the WS to 'workgroup', and then again to the 'old' NT4 domain. On the WS, Win7 says 'failed', but in the server manager under NT4, the machine is displayed, and I can click onto the machine, I can see the shares, the connected users, it looks so far pretty normal, except that you are not able to login onto the domain using the new Win7-WS. I know that NT4 is not supported, but is there a way to put that to work? Migrate our domain is not made in 5 minutes :-) Regards Markus

As stated above, there is NO workaround.. please view this document: http://technet.microsoft.com/en-us/library/ee681706%28WS.10%29.aspx Get started to plan your Server 2008 R2 upgrades, or not to use windows 7..