Web Client - How to open applications by their own.

I m using the following attachment handling code in my web client <? // supposing that: // $encoding = 'BASE64'; // $pid = attachment's pid; // $file = attachment's file name; // $size = $object->bytes; // $type = $object->type; // $subtype = $object->subtype; //....... $attch = imap_base64(imap_fetchbody($mbox, $id, $pid)); //....... $types = array("text", "multipart", "message", "application", "audio", "image", "video", "other"); $cont_type = $types[$type]."/".$subtype; header("Content-transfer-encoding: binary\n"); header("Content-type: $cont_type\n"); if (strstr($_SERVER["HTTP_USER_AGENT"], "MSIE")) header("Content-Disposition: filename=$file\n"); // For IE else header("Content-Disposition: attachment; filename=$file\n"); // For non-IE browsers header("Content-length: $size\n" ); print $attch; ?> Regardless the nature of the attachment, things are happening expectedly (as far as I tested) as long as the SAVE button of the browser's save-file dialog is clicked. The OPEN button works fine as well, for browser compatible files such as .jpeg, .gif, .txt, etc... But when it's matter of opening per ex. a MSPoverPoint *.pps slide-show file as attachment through the browser's save-file dialog (well, the button is there and any user may click it) the smooth running web client turns into a PoverPoint application opened through the browser's window with an empty project in design view. Wrapping above code with <? $tmpfname = tempnam (0, 0); $fp = fopen($tmpfname, "w"); fwrite($fp, $attch); fclose($fp); ................... unlink($tmpfname); ?> didn't help too much. Would there be a way to force the browser to download the attachment in a temporary location and launch the application (MSPowerPoint in this case) by its own? Okar