SBS 03 / Exchange Server changing private side IP range from current

It would depend on the subnet mask and or routing tables.  If your subnet is 255.255.255.0, then the first three numbers are the network, and the last octet is your device.  If this was the case, when you change your internal IP to 192.168.1.x to 192.168.x.x, then the 192.168.x.x is no longer in the same network and will not be able to communicate to anything else.  

In order to make that work, you would need to have a subnet of 255.255.0.0 -or more commonly found- a route on your network to tell traffic from the 192.168.1.x network  to get to the 192.168.x.x network.

I forgot about that, the reason this has to be changed is when our clients log in via VPN connection from either home or from a hotel they often find themselves using the same IP range as the business. Changing their settings at home router is easy to resolve, but it's our road warriors that we can not change, hence the reason for changing the IP range.

It is still better to have your VPN people get a different IP via the VPN server, to deal with this, don't allow your VPN to relay DHCP information to your internal network.
http://technet.microsoft.com/en-us/library/cc736357(WS.10).aspx

is a technet on it.  and if you must, then you can change all of your DHCP and internal network to reflect this new IP scheme you want.

let me look this over tsaico and I will get back to you

I found that even I change the IP range from 192.168.1.1 to 192.168.5.1 the subnet mask will still be in the same range as 255.255.255.0. But this also didn't answer the rest of my question as to would me changing the company's IP range have any affect on the Exchange Server.

I figured it out of myself