Assume that you click Edit aCopy to create a copy of a control template in Blend or in XAML Designer on a computer that has Microsoft Visual Studio 2012 Extension SDK installed. In this situation, a blank copy of the control template is created.
To resolve this issue, follow these steps:
Exit Visual Studio 2012 if it is running.
Download and install the latest release of the Visual Studio Update from the Microsoft Download Center. The following file is available for download from the Microsoft Download Center:
For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:
119591 How to obtain Microsoft support files from online services
Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.
You do not have to restart your computer after you install this package.
To work around this problem, follow these steps:
Open the Generic.xaml file from the following location:
Microsoft Visual Studio Ultimate 2012, Microsoft Visual Studio Premium 2012, Microsoft Visual Studio Professional 2012, Microsoft Visual Studio Express 2012 for Web, Microsoft Visual Studio Express 2012 for Windows 8