.: Response to PM :.
Yes, it can be done and if you think about it, it is done quite a bit. The Windows Updater for example installs patches and hotfixes directly into the OS without requiring the user to download a given file. The problem is, (without the use of some activeX control) you can't simply give the user XYZ web page and start an install into their machine. (Imagine the kinds of malicious code that could be sent to any given Internet user if this were possible).
In the case of Microsoft Windows Update the user must first download BITS and install it on their system before they can go to the WindowsUpdate webpage to install all of the updates. You will need to do the same thing, you are going to need to distribute some sort of executable to users that can initiate a download from your website or create some form of ActiveX control to embed directly in your website.
There are implications with either route. In the case of the distributed exe you open yourself up to piracy but with an online installer you have the chance that a user could get disconnected during a transfer or the install doesn't work when they have already paid you for XYZ application.
Lastly, there is no silver bullet to prevent piracy if there was Microsoft, Adobe, Sun, etc would have figured it out by now; it is just something you need to come to terms with.
Read this if you want to know how to get a correct reply for your question:
.: Wrox Technical Editor / Author :.
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