Question : Help needed on setting up correct rules for the Forefront TMG 2010 Firewall2010

Could please some ISA/Forefront TMG guru tells me on how my external client (Ext. Client) can successfully access ‘Web Server 1’ which has been published with web access rule through TMG firewall (please refer to the diagram). TMG simply drops the traffic from ‘Ext. Client’ with massage saying that IP address has been spoofed. I did a simple test, temporary I connect ‘DMZ Client’ on to the TMG perimeter network and, modified host file on ‘DMZ Client” with host name of the published web server (Web Server1) to point to the Perimeter NIC of the TGM and EVRYTHING works fine!

Q.1 – Tell me please that with my currents scenario it is possible to “fix” my problem?
Q.2 – What exactly needs to be done to enable ‘Ext. Clients’ to have access to the ‘Web Server 1’
Q.3 – If we can successfully fix Q.1 and Q.2 we are hoping to start creating new TMG rules to allow OWA and SharePoint services to our external users.

Additional Information: This Company originally had only one ISP connection (ISP-1) and one Linux firewall (Firewall-1). Firewal-1 is connected through very fast but very expensive fibre internet connection and has static publicly registered IP address. To make life a bit easy on publishing internal web sites (OWA, SharePoint, Company Portal, etc.) externally, they invested money on brand new Forefront TMG 2010 server. Cheap ADSL connection was purchased mainly for the one reason - not to waist expensive fibre connection on downloading patches and other stuff. ADSL connection has dynamic IP address and will be used primarily by IT department staff only. Company users have and will be using internet access through the Firewall-1 only.

Any advice will be greatly appreciated.

Attachments:

TMG-2010.jpg (59 KB) (File Type Details) 

Company Firewall Topology

Answer : Help needed on setting up correct rules for the Forefront TMG 2010 Firewall2010

try to find the Relative Path just do one thing when ever you want to check the relevant  path any of the file just drag and drop that file in any of the html File you will find the relevant  path and just use this....
This is the Standard Rule of the finding any file relative path...in web page.....