AN ARTICLE on tech site Kuro5hin claims that the Internet Explorer 7 web browser fiddles with downloads from GMail by altering the download URLs and requesting zipped versions of files in Apple's file formats like Quicktime.

Caleb from Austin, TX who goes by the nickname riddlemark on the tech site recently wrote an intriguing piece entitled "Microsoft Plays Dirty With Gmail" describing his surprise to see that IE7 always downloaded .mov files sent as GMail attachments as compressed .zip files, whereas clicking on the same download link in Firefox and other browers gave him the .mov file straight from the cooker without a chaser.

He suggested that "either Google is giving IE7 a modified URL or Microsoft has coded IE7 to look for a list of extensions within Gmail and modify the attachment URL," adding that, "The first option seemed highly unlikely."

The problem, following Caleb's logic, is that hard-coding a URL from a third party site into an executable program and worse, applying changes to the URL constructed, is a recipe for disaster. First, because Microsoft does not control GMail, and GMail as an AJAX application can change any minute. And the second problem, is that we tried but were unable to reproduce the behaviour he describes.

It could also well be GMail which, based on the user agent presented by the browser, acts differently. For instance, for the sake of argument it could be that the GMail application wants to ensure that mov files are downloaded instead of playing "in-line" inside the browser by a plug-in. The effect of having media players installed on the system which also install activeX browser hooks can't also be discarded.

Installing Quicktime for Windows, for instance, has the nasty habit of messing up mp3 file downloads. After you install Quicktime, if you want to c lick on a link to download an mp3 file, you often get the audio file loaded inside the quicktime player plug-in, inside the browser - often with autoplay!. This is one of the reasons why this scribbler is very reluctant about installing the Media Player from the Church of Cupertino.

But back to the subject: we e-mailed a couple .mov files to one of our GMail accounts and loaded it with MS IE 7 on XP SP2. Clicking on the attached file actually initiated a .mov file download, not .zip as reported by the referenced article. When it comes to the technical details, Caleb wrote that IE7 switched the download URLs on its own: "I found an option to download attachments as a zip file. Simply replace 'disp=attd' with 'disp=zip' in the attachment URL. IE7 was changing this to 'disp=indzip' for the same result; on its own."

Well, we're pleased to report that if this ever happened, it isn't happening any more. The current download URLs have 'disp=safe', not 'attd' nor 'zip'. Our IE7 in the test system is at build#7.0.5730.11, and we even used 'safe mode' -iexplore.exe -extoff- as suggested by the story author.

Moral of the story: in the server-side web-applications world, before sentencing your software, be suspicious of the AJAX code. µ