IIS IDA/IDQ Path Disclosure

IIS 4.0 allows a remote attacker to obtain the real pathname of the document root by requesting non-existent files with .ida or .idq extensions. An attacker may use this flaw to gain more information about the remote host, and hence make more focused attacks.
Select 'Preferences ->Home directory ->Application', and check the checkbox 'Check if file exists' for the ISAPI mappings of your server.