No, it is not possible with a standard ClickOnce deployment scenario.
ClickOnce is a sandboxed installation on the client side. It will not know about version 1.0 that's already installed. It is simply going to check to see whether its GUID has already been installed via ClickOnce and if so update it, but only if the previous version was deployed via ClickOnce.
In your case, if the user installed Version 1.1, both versions will be installed side by side. Version 1.0 will not be updated, because ClickOnce doesn't know there's an association since it was deployed via a different method. If they don't want version 1.0 anymore, they'll need to remove it manually. Once you've got version 1.1 deployed via ClickOnce, subsequent updates will work correctly.
Don't think of ClickOnce as something you're "including", think of it as a method of deployment.
Alternatively:
I should clarify that what you're looking for is not possible with standard ClickOnce deployment. However, you mentioned you're going to send them an initial setup file. In that case you may have a workaround that's possible:
- Script the setup file to remove the version 1.0 installation automatically
- Script the setup file to launch the ClickOnce installation.
For subsequent updates, simply point the user to the "pure" ClickOnce setup package, and your updates should work fine.
Best Answer
If you have to stay with Visual Studio 2005, your only option is to write code to create the icon. Here's how to do it. However, be aware of the fact that if a user uninstalls your application, the desktop icon won't get removed.
If you ever upgrade to Visual Studio 2008 SP1, you'll get this feature out of the box.