Hi, first which OS do you use, I find some articles about this problem:
If you use Windows Server 2003
FrontPage 2002 Server Extensions from Microsoft is required for publishing applications to a Windows Web server that uses HTTP.By default, Windows Server 2003 does not have FrontPage 2002 Server Extensions installed. If you want to use Visual Studio to publish to a Windows Server 2003 Web server that uses HTTP with FrontPage 2002 Server Extensions, you must install FrontPage 2002 Server Extensions first. You can perform the installation by using the Manage Your Server administration tool in Windows Server 2003.
http://msdn2.microsoft.com/en-us/library/ms228998.aspx
If you use Vista
When you publish from Visual Studio to an http address, VS uses Frontpage Server Extensions (FPE) to create the virtual directory and copy the files to it. When logged in as an admin, VS will not be running with admin privilege by default. As a result, when you try to publish a ClickOnce app you will get an obscure error that says that FPE is not installed on the server. Specifically:
"Failed to connect to 'http://localhost/WindowsApplication3/' with the following error: Unable to create the Web 'http://localhost/WindowsApplication3/'. The Web server does not appear to have the FrontPage server extensions installed."
The solution is quite simple: you need to run VS as an admin. To do this, you can right click on the shortcut to VS from the start menu and select Run as Administrator.
For more information, please check this article
http://briannoyes.net/PermaLink.aspx?guid=435524e7-340c-4b4b-933d-a1c38d27e8ea
If you have any further question, feel free to let me know.
Best Regards
Gavin