Can Windows Server 2003 (Enterprise Edition) coexist with SBS 2003

Yes, you could. But it could get complicated. Your easiest approach would be to build a new domain on the SBS 2003, and then migrate the Enterprise Edition server over to that new domain as well as all your workstations and users.

-Matt

Yes, however, it's not wise to do so.  SBS is designed to be the first server installed and it MUST be the FSMO master domain controller (if it's not made the fsmo master DC, it will start rebooting itself every hour after 7-21 days because you will be violating the license).

The best way to do this is to install SBS as a new domain and migrate your existing server into the SBS domain (SBS CAN have as many servers as you like, but ONLY ONE may be SBS due to the FSMO master roles).

As suggested above it is not wise to do so. SBS will start shutting down the server every 60 minutes after a while after complaining about having two domain controllers in the network.  You shold follow Leew's suggestion. Have your sbs 2003 domain controller and migrate the win 2003 in to that domain.

fm

Can I install SBS, join the ADS of existing Windows 2003 server, demote the Windows 2003 to ADC and then transfer the FSMO to the SBS Server. Will this work?

If possible I want to avoid creating a new domain since I have the older server since a few months and many things have already been setup on it.

Thanks,
Riaz

Yes, you can. As we've already stated, it's not recommended since SBS works best when you start with a clean domain. However, it is possible and Microsoft have a document which details specifically what you need to do to get an SBS running properly in an existing domain: http://support.microsoft.com/kb/884453.

That article details how to promote the SBS as a DC and transfer FSMO roles manually, which is what you must do to integrate it into an existing domain.

-Matt

http://support.microsoft.com/kb/884453 is not opening for some reason. Can I remove ADS from my Windows 2003 server, install SBS and later join the Win2K3 server to the domain?

Thanks
Riaz

Thank you and all the other experts for their valuable advice.