**Visual Studio Ultimate 2013 v12... update 5, .NET v4.6...**

**New to the programming of Windows Phone in Visual Studio**

**Setup:** File > New Project > Templates > Visual Basic > Store Apps > Windows Phone Apps > Blank App (Windows Phone)

Trying to keep this simple and focused on the specific problem:

**Steps Taken:** In the template project's MainPage.xaml the following line (attribute) was added to the opening < page > element.

```
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"

```

The project was successfully built. Then the opening element was changed from

```
< Page > to < phone:PhoneApplicationPage >

```

**Error Messages:**

```
The name "PhoneApplicationPage" does not exist in the namespace "clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone".
and
Unknown type 'PhoneApplicationPage' in XML namespace 'clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone'
'Sub Main' was not found in 'App1'.
'InitializeComponent' is not declared. It may be inaccessible due to its protection level.

```

I listed all of the errors in case I'm misunderstanding what the build is trying to tell me. I'm thinking the problem is a Reference and the other errors are consequences of the Reference problem. If it is the other way around please let me know.

I have a downloaded source code phone project in C# from the book I'm studying for WPF. It builds just fine using the < phone:PhoneApplicationPage > opening element. I figure that means the libraries are in fact on the development PC.

I believe this to be a simple problem making sure the project references are properly set, but after trying for some time to fix it I can't figure it out.

During my research I found that certain things changed from Windows Phone 8 to Windows Phone 8.1. The Package.appxmanifest seems to be the place to set many things previously set in XAML, but I didn't see a place to enable < phone:PhoneApplicationPage >; I presume that really needs to be taken care of by a proper Reference.

My research into the 2 projects (downloaded C# code and my VB templated code) revealed among other things a difference in the Solution Explorer References node. In the C# project it says:

```
.NET for Windows Phone
Windows Phone

```

In the VB template code it says:

```
.NET for Windows Store apps
Windows Phone 8.1

```

When I look in Object Explorer I can find Microsoft.Phone and all its children including Microsoft.Phone.Controls which includes PhoneApplicationFrame.

So I don't understand why I can't use that Class in this basic built-in template project.

I'm familiar enough with References, but clearly not an expert. I don't know what to do next.