If you are not sure what WebDAV is, please refer to on Sitecore Developer Network.
Briefly, quoting this doc:

WebDAV allows users of Web clients such as browsers to manage files on Web servers using Web protocols such as HTTP or HTTPS. With WebDAV, users can drag-and-drop files between the Windows desktop and the browser. I would recommend disabling this feature on the Content Delivery side as WebDAV is not expected to be used there.

It also makes sense disabling this feature on the CMS side if you are not planning on leveraging this feature at all. This will reduce the number of log files written to the /data/logs folder and get rid of the errors in the main log files generated if WebDAV is misconfigured.

Here are the steps:

  1. Remove WebDAV config references within <log4net />:
 1: <log4net> 
 2: <appender name="LogFileAppender" type="log4net.Appender.SitecoreLogFileAppender, Sitecore.Logging"> 
 3: <file value="$(dataFolder)/logs/log.{date}.txt" /> 
 4: <appendToFile value="true" /> 
 5: <layout type="log4net.Layout.PatternLayout"> 
 6: <conversionPattern value="%4t %d{ABSOLUTE} %-5p %m%n" /> 
 7: </layout> 
 8: </appender> 
 9: <!--<appender name="WebDAVLogFileAppender" type="log4net.Appender.SitecoreLogFileAppender, Sitecore.Logging"> 
 10: <file value="$(dataFolder)/logs/WebDAV.log.{date}.txt" /> 
 11: <appendToFile value="true" /> 
 12: <layout type="log4net.Layout.PatternLayout"> 
 13: <conversionPattern value="%4t %d{ABSOLUTE} %-5p %m%n" /> 
 14: </layout> 
 15: </appender>--> 
 16: <root> 
 17: <priority value="INFO" /> 
 18: <appender-ref ref="LogFileAppender" /> 
 19: </root> 
 20: <!--<logger name="Sitecore.Diagnostics.WebDAV" additivity="false"> 
 21: <level value="INFO" /> 
 22: <appender-ref ref="WebDAVLogFileAppender" /> 
 23: </logger>--> 
 24: </log4net> 
  1. Remove WebDAV config references within <system.webServer />:
 1: <!--<remove name="WebDAVModule" />-->
 3: <!--<add name="WebDAVRoot" path="*" verb="OPTIONS,PROPFIND" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v2.0.50727\aspnet_isapi.dll" resourceType="Unspecified" preCondition="classicMode,runtimeVersionv2.0,bitness32" />
 4: <add name="WebDAVRoot64" path="*" verb="OPTIONS,PROPFIND" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v2.0.50727\aspnet_isapi.dll" resourceType="Unspecified" preCondition="classicMode,runtimeVersionv2.0,bitness64" />
 5: <add verb="*" path="sitecore_webDAV.ashx" type="Sitecore.Resources.Media.WebDAVMediaRequestHandler, Sitecore.Kernel" name="Sitecore.WebDAVMediaRequestHandler" />-->
  1. Remove WebDAV config references within <httpHandlers>/>:
 1: <!--
 2: <add verb="*" path="sitecore_webDAV.ashx" type="Sitecore.Resources.Media.WebDAVMediaRequestHandler, Sitecore.Kernel" />
 3: -->
  1. Finally, you can delete the Sitecore.WebDAV.config file from webroot/App_Config/Include.