<p>I have the following configuration, but I have not able to find any documentation on how to set a maximum backup files on date rolling style.  I know that you can do this with size rolling style by using the maxSizeRollBackups.</p>

<pre><code>&lt;appender name="AppLogFileAppender" type="log4net.Appender.RollingFileAppender"&gt;
    &lt;file value="mylog.log" /&gt;
    &lt;appendToFile value="true" /&gt;
    &lt;lockingModel type="log4net.Appender.FileAppender+MinimalLock" /&gt;
    &lt;rollingStyle value="Date" /&gt;
    &lt;datePattern value=".yyMMdd.'log'" /&gt;
    &lt;layout type="log4net.Layout.PatternLayout"&gt;
      &lt;conversionPattern value="%d %-5p %c - %m%n"  /&gt;
    &lt;/layout&gt;
&lt;/appender&gt;
</code></pre>

Not sure exactly what you need.  Below is an extract from one of my lo4net.config files:
```
```
<appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
    <param name="File" value="App_Data\log"/>
    <param name="DatePattern" value=".yyyy-MM-dd-tt&quot;.log&quot;"/>
    <param name="AppendToFile" value="true"/>
    <param name="RollingStyle" value="Date"/>
    <param name="StaticLogFileName" value="false"/>
    <param name="maxSizeRollBackups" value="60" />
    <layout type="log4net.Layout.PatternLayout">
      <param name="ConversionPattern" value="%r %d [%t] %-5p %c - %m%n"/>
    </layout>
  </appender>
```
```