The worker process has failed to load application configuration file: %1

This Error event indicates the Microsoft Exchange Transport service couldn’t load the EdgeTransport.exe.config application configuration file because of a file syntax error.

The EdgeTransport.exe.config file is an XML application configuration file that is located at C:\Program Files\Microsoft\Exchange Server\Bin. EdgeTransport.exe.config is associated with the EdgeTransport.exe file. EdgeTransport.exe and MSExchangeTransport.exe are the executable files that are used by the Microsoft Exchange Transport service. This service runs on every Hub Transport server or Edge Transport server. Changes that are made to the EdgeTransport.exe.config file are applied after the Microsoft Exchange Transport service is restarted.

The following example shows the typical structure of the EdgeTransport.exe.config file:

<configuration>

<runtime>

<gcServer enabled=”true” />

</runtime>

<appSettings>

<add key=”Configuration Option” value=”Value” />

…

</appSettings>

</configuration>

You can add new configuration options or modify existing configuration options in the <appSettings> section. The parameter names in the <add key=../> section are case sensitive.

If a specific parameter is missing, or if the EdgeTransport.exe.config file is missing, the default values for all available parameters are used when the Microsoft Exchange Transport service is started.

To resolve this error, follow these steps:

1. Rename the existing EdgeTransport.exe.config file in the C:\Program Files\Microsoft\Exchange Server\Bin directory to EdgeTransport.exe.bad.

2. Make a copy of the EdgeTransport.exe.config.template file that also exists in the C:\Program Files\Microsoft\Exchange Server\Bin directory. Name the copied file EdgeTransport.exe.config. The template file contains the default values for all parameters.

3. Compare the values in the old EdgeTransport.exe.bad file to the new EdgeTransport.exe.config file. Verify that any customizations that you might have made to the values of any parameters in the <appSettings> section are incorporated into the new file.

4. Restart the Microsoft Exchange Transport service.

If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.