This article describes how to reinstall Microsoft® Forefront™ Threat Management Gateway, Medium Business Edition on Windows® Essential Business Server Security Server.  This may be necessary as a last-effort troubleshooting step or to repair a damaged installation of Forefront TMG.  The steps in this article will, of course, cause loss of network connectivity until Forefront TMG is reinstalled and reconfigured.

Important: Before using these steps, it is recommended that you make a complete backup of the Security Server.

There are four steps to uninstalling and reinstalling TMG on EBS:

1. Backup the existing firewall settings
2. 2. Uninstall Forefront TMG from Security Server
3. 3. Install Forefront TMG on Security Server
4. 4. Restore the Forefront TMG firewall configuration

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