由于存在三个Web应用程序，因此我认为这三个Web应用程序具有不同的虚拟目录.

因此，您可以在首页中直接输入这三个Web应用程序的网址

Since there are three web applications and i assume that these three web apps had different virtual directories.

So you can directly enter the url of these three web applications in you home page

Ex.

<a href="http://Mycomputername/Webapp1/home.aspx"  runat="server" />

<a href="http://Mycomputername/Webapp2/home.aspx"  runat="server" />

<a href="http://Mycomputername/Webapp3/home.aspx"  runat="server" />