I would like to be frugal as possible with this setup. I have servers with Server 2003/2008 Standard that I can use, but I really do not want to spare their operating system / licenses / etc for the sake of a phone system which doesn't need any of the Windows Server services in fact. I'd fear running anything except the bare minimum provided and keep myself from ever getting a wild notion to make it a redundant DNS server or something. :lol: So this is the question: Would I lose anything, at all, by deciding to slap Windows 7 Professional on there and securing it down and reducing the services running to a bare minimum? I assume all hardware, connectivity, and functionality is the same. Microsoft limits the number of active CIFS connections to the system, but I am doubting that this is a factor in 3CX. I am new to this system: in fact I am just quoting it today. I will experiment with it sometime this week. So I really want to do my homework. If I have to dump the extra bucks for a true-server-OS, I will without a doubt. So do me a favor and tell me why or why not to use Windows Server 2008. Doing this will allow me to buy a new rackmount box for this system rather than repurposing the old "redundant" domain controller box that I decided to take down three months ago. Thank you in advance!