Tom, There is a few options here. All of these are hacks, for security reasons outlined by others. Would it be an idea to give the file a costum mime-type and assign that to a specific program? You don't say whether you (1) need the actual file on the client computer or (2) could also start parsing the data in the actual application in which you will use the file later on anyway Setting the mime type is done in the way Dieter Maurer exposed in an earlier response: <dtml-call "RESPONSE.setHeader('Content-Type','application/binary')"> where application/binary has to be you custom type you have to invent if (2) you'll be set if you assign this mime type to the application in the browser's preferences if (1) you will have to make a simple program (a simple (python)script would be enough) that saves this to the filesystem to a location the program knows about hth Rik