Application Server Administration job failed for service instance:Access to the path 'C:\Windows\system32\drivers\etc\HOSTS' is denied.

Application Server Administration job failed for service instance Microsoft.Office.Server.Search.Administration.SearchServiceInstance (db7e7060-eba7-4b6c-b09e-242978fa6e97).
Reason: Access to the path 'C:\Windows\system32\drivers\etc\HOSTS' is denied.

Having this error?

Read on and you will know why Search writes in the host file and how to give access to the host file.

First of all, Search service writes in the host file when you use a dedicated server for crawling 
For more details - sharepoint 2007 search writes wrong IP in host file

Wondering if you need to use a dedicated server? Read this simple and useful article - Configure a dedicated front-end Web server for crawling (Office SharePoint Server 2007)

In case you need to keep a dedicated server for crawling, to fix the issue with access to host file, do following:
 Set permissions for group WSS_Admin_WPG on host file
Make sure that you Set "Modify" BUT NOT "Full control" (otherwise Search deletes HOST file)