Inability to use EventLogAppender with ASPNET

[Matthew Brown]

With log4net internal debugging turned on, an attempt to create an EventLogAppender for a web application is failing:

[3616] log4net: XmlHierarchyConfigurator: Setting Property [Layout] to object [log4net.Layout.PatternLayout]
[3616] log4net: XmlHierarchyConfigurator: Setting Property [LogName] to String value [Application]
[3616] log4net:ERROR XmlHierarchyConfigurator: Could not create Appender [EventLog] of type [log4net.Appender.EventLogAppender]. Reported error follows.
[3616] System.Security.SecurityException: Requested registry access is not allowed.
[3616]    at Microsoft.Win32.RegistryKey.OpenSubKey(String name, Boolean writable)
[3616]    at System.Diagnostics.EventLog.FindSourceRegistration(String source, String machineName, Boolean readOnly)
[3616]    at System.Diagnostics.EventLog.SourceExists(String source, String machineName)
[3616]    at System.Diagnostics.EventLog.SourceExists(String source)
[3616]    at log4net.Appender.EventLogAppender.ActivateOptions()
[3616]    at log4net.Repository.Hierarchy.XmlHierarchyConfigurator.ParseAppender(XmlElement appenderElement)
[3616] log4net:ERROR XmlHierarchyConfigurator: Appender named [EventLog] not found.
[3616] log4net: XmlHierarchyConfigurator: Hierarchy Threshold []
[3616] log4net: AppenderSkeleton: Finalizing appender named [EventLog].

The FAQ on the log4net site says that the ASPNET account has permission to write to the event log if created already. Just to be sure, I made sure to add ASPNET and IUSR_machinename to the Administrators group, but this does not work either.

Here is my configuration:

<appender name="EventLog" type="log4net.Appender.EventLogAppender" >
            <layout type="log4net.Layout.PatternLayout">
                <conversionPattern value="%date [%thread][%mdc{AspNetSessionID}] %-5level %logger - %message%newline" />
            </layout>
            <logName value="Application"/>
        </appender>

        <root>
            <level value="ALL" />
            <appender-ref ref="LogFileAppender" />
            <appender-ref ref="EventLog" />
        </root>

Sorry if this is a silly newbie question, but I couldn't find much out there on configuring/using EventLogAppender besides "its tough". Can anyone help?

Thanks,
Matt Brown