Scott Hanselman has recently discussed the ways that an application can auto-update itself.

He’s only discussing the nice side of the auto-update, assuming that the app will behave correctly and predictably. Here’s my take: if you can’t implement this functionality right, don’t even try, you’ll only annoy your users.

Examples of auto-update done right:

• Reflector, besides from being an all-around cool tool, updates seamlessly and with the lest fuss
• Eclipse, even though it consists of a million plug-ins and sub-platforms and whatnot
• Paint.net, including auto-update to and from a beta version
• Windows Live Messenger, notifies you, downloads and installs, simple and effective
• Firefox, downloads the update in the background, just restart and that’s it

Examples of auto-update done bad:

• Samsung PC Studio, where the update consists of the individual downloads of each and every DLL and EXE (I kid you not), judging by the look of the progress bar uncompressed; takes a lot of time on my 15Mb connection, but at least it works
• Nero 7 Premium, confusing UI, mindless questions, does not work and it’s not obvious why; looking from the Process Explorer it does establish the HTTP connection(s) to the French mirrors (OK, at least it got right that I live in France) but then nothing happens and it declares “download problems” – “very” informative

If it takes more trouble and nerves to use the auto-update, please don’t bother. Just link to the Web page with the info on the latest version and I’ll download it myself, thank you very much.