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Routing and Remote Access cannot access DHCP

I have an SBS 2003 server with ISA 2004.  I am trying to setup VPN access with RRAS using DHCP.  However, everytime I try to connect I get the Automatic Private IP Address assigned to the client and the following error in the System event log:

Unable to contact a DHCP server. The Automatic Private IP Address will be assigned to dial-in clients. Clients may be unable to access resources on the network.

I can get around this issue temporarily by setting up a static address pool in RRAS, but anytime I reboot the server RRAS defaults back to DHCP and cannot reach DHCP on the server.

I have a T1 coming into my external NIC with a public IP assigned to it.  The second NIC has the private IP assignment out to the internal network.

I have tried the following:

1.  Configuring Remote Access using the wizard in the To Do List in SBS.  (I have used this on other SBS servers and everything works fine without having to configure anything in ISA).

2.  Enabling DHCP Relay for ISA Firewall VPN Clients as indicated at http://tinyurl.com/odabc.

3.  Using a different NIC for my external network card.

Ideally, RRAS would use DHCP, but at this point I would be happy with static assignments if I could get it to stick.

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1 Solution
Jeffrey Kane - TechSoEasyPrincipal ConsultantCommented:
As you can see from the comments in this forum post:  http://forums.isaserver.org/m_2002009599/mpage_1/key_/tm.htm#2002010305

this can be caused by having an IP Address range which is the same in two different sources.  ie, if your server's range matches the remote connections.  

Also note the coment about "Network Services-DHCP".

initialitAuthor Commented:
Here is the solution as provided by Microsoft:

1. Make a note of the IP information on all of the network cards.
2. Run the following command to reset tcp/ip: Netsh int ip reset c:\ipreset.txt
3. Reboot the server into Directory Services Restore Mode.
4. All of the nics will be reset to use DHCP.  Reconfigure the IP information on the appropriate nics.
5. Reboot the server into Normal Mode.
6. Configure VPN in ISA to assign addresses from DHCP.
7. Test the VPN connection to see if you receive an address from DHCP.
Jeffrey Kane - TechSoEasyPrincipal ConsultantCommented:

Thanks for posting back... I was thinking that could be a possibility but lost track of this question.  There is a KB article that describes some of this:  http://support.microsoft.com/kb/317518

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