Hi windev1oafi,
Which windows OS version are you using? Could you please tell us the detailed error information when you try to create the Windows Phone 8.1 project in the Visual Studio Community 2015 RC? Besides, please check the following image about the Visual Studio
2015 RC support for Windows universal, Windows Store, and Windows Phone app development:

For more information, please try to refer to:
https://www.visualstudio.com/en-us/products/visual-studio-2015-compatibility-vs.aspx .
Best Regards,
Amy Peng
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