1. A computer-implemented method for handling CIFS (Common Internet File System) communication between a client computer and a server computer, the method comprising: providing a CIFS proxy between said client computer and said server computer; providing, using said CIFS proxy, to said server computer a client IP address that is associated with said client computer as a proxy-to-server source IP address when communicating from said proxy to said server computer; providing, using said CIFS proxy, to said client computer a server IP address that is associated with said server computer as a proxy-to-client source IP address when communicating from said proxy to said client computer; monitoring, using said CIFS proxy, client requests and server responses, said client requests being originated from said client computer and destined for said server computer, said server responses being originated from said server computer and destined for said client computer; intercepting, using said CIFS proxy, an open-file request provided by said client computer for opening a file stored in said server computer; performing, using said CIFS proxy, open-file processing on said file or a copy of said file; determining, using said CIFS proxy, that a first command provided by said client computer is for closing said file; performing, using said CIFS proxy, close-file processing on said file or a copy of said file after said determining; and issuing, using said CIFS proxy, a second command to said server computer after said performing said close-file processing using said client IP address as said proxy-to-server source IP address, said second command preventing said server computer from saving said file and causing said server computer to save a null file.