Abstract: An anti-virus program executes simultaneously with another anti-virus program by accessing a function (target) driver in the driver model directly instead of traversing each filter driver in the driver model as is conventionally done. The filter driver component of the anti-virus program avoids deadlock and infinite execution loops by bypassing filter drivers of other executing anti-virus programs and other filter drivers and going straight to the driver that will be performing the specific function, such as opening a file for scanning. This is done by having the filter driver component of the anti-virus program obtain directly the handle of the function driver that will perform the function needed by the anti-virus program and thereby avoiding the filter drivers of other programs, specifically other anti-virus programs, that can prevent completion of the required function.