When check the [sign the Xap File] checkbox, build project failed due to
signtool.exe not found.
Follow these steps:
1. Make sure windows SDK is installed: http://msdn.microsoft.com/en-us/windowsserver/bb980924.aspx
2. Make sure this path is contained in the system environment variable [path] (this path is for .net 4.0/4.5)
C:Program Files (x86)Microsoft SDKsWindowsv8.0AinNETFX 4.0 Tools
And this one:
C:Program Files (x86)Microsoft SDKsWindowsv7.0ABin
3. Make sure the tool signtool.exe is there, if not download one from internet.