I have an SBS 2003 server that runs an application that we wish to keep around. However, our new system will run on Server 2012 Standard. The application cannot be run on 2012, or even 2008 R2. It must run on Server 2003. Putting aside the fact that 2003 is EOL, can I run my SBS 2003 system along side my 2012 DC in the same domain, possibly as a member server? Or will SBS do it's hourly reboot thing because it detects other DC's?