Hi, we have a network monitoring program (opennms) that check status of web service doing an HTTP 1.0 request to port 80. Plesk answer to this kind of request as follows: HTTP/1.1 500 Internal Server Error Content-Length: 93 Content-Type: text/html Server: Microsoft-IIS/6.0 Date: Mon, 19 Apr 2004 09:49:08 GMT Connection: close <html><head><title>Error</title></head><body>The system cannot open the file. </body></html>Connection closed by foreign host. This happens only on the IP where Plesk domains are configured. So it is not an IIS problem. I think this behaviour does not follow the HTTP RFC. Thanks in advance for your help.