Hello everyone I am kinda new to Windows Server configuration and I hope you can give me some input. Currently we have 5 servers in our company, Windows 2003, Windows 2003r2, Windows 2008, Windows 2008r2, Windows 2012. Windows 2008r2 was our Primary DC 6 months ago, and when we purchased a new Windows 2012 server, we have allow this new server to take over the role of a DC. Now we encounter some hardware issue on the 2012 server and wanted to reconfigure the server. I have read books on Windows 2012 Installation and Configuration etc but I still have 3 confusions. 1) Can I simply backup and then reformat my Windows 2012? After which I can do apply the AD? I will do it over the weekend. 2) Since there are different versions of Windows Server OS, what is the forest level and domain level that I should select after reinstalling the 2012 server? 3) After I had reformatted, and use back the same domain name, do I have to get all my colleagues PC to rejoin back the same name domain?