I have connected our office which uses a SBS 2003 server for DHCP and control of the domain etc via a 2820VN to a remote office using anouther 2820VN

I have set up a vpn connection conection from the remote office dialing into the main office and can use any machine, printer i want over the VPN fine but when in the office trying to use a machine in the remote office i am not able to i think it has something to do with our SBS server not knowing the ip address and DNS of the remote office can anybody help please

I have same scenario (SBS2003 in 'central office' and 3 remote offices. Full subnet access is available from/to any subnet, so what you ask is do-able.

I don't use my SBS as a dhcp server, although i dont think that's relevant here although you might want to keep an eye on any 'gateway' address your dynamic clients get issued.

Me, I set the gateway address of all machines in the central office to be their local draytek router. Then, for each remote subnet VPN definition file in your draytek's VPN setup (VPN->LAN-LAN->(locations)), you should ensure that at the extreme bottom left section of that VPN's definition has entries which whill allow routing of matching packets back to the remote VPN subnet eg:

My WAN IP: 0.0.0.0
Remote Gateway IP: 0.0.0.0
Remote Network IP: 192.168.x.0
Remote Network Mask: 255.255.255.0

After changing the above, if you re-make your VPN tunnel between the central office and the remote office, and then reboot a central office computer (and confirm that is is using the central office router as its gateway) then you should be able to ping the router at the remote office (and hopefully anything hanging off the remote subnet). If you cannot ping, then maybe firewalls on the central office computer you are using are preventing you from accessing the remote subnet (actually, that might already be an issue you should eliminate). Alternatively, you could use the Central Office's router's own Ping utility (on the web GUI) to ensure whether the routers can themselves route to the remote subnets .... because if your central office router [gateway] cannot ping routers on remote subnets, then nothing in your central office subnet will be able to connect to remote subnets).

So, i think you must be quite close to solving this.

Make sure in the DHCP settings in the router at the remote sites set the primary DNS to the SBS server in your main site - that way remote machines should register themselves in the internal DNS