Build Failed. See the build log for detail

Question

I create a new project, click compile, and get this error:

Build Failed. See the build log for details.

In the build log there i

Answer 1

I had the same problem after upgrading Xamarin, and in my case it happened even for a x86/desktop Console Application. Turned out to be because I didn't have 4.5.1, which was required by the newer version (I had only 4.5 I think).

I found this entry in the log:

Unregistered TargetFramework '.NETFramework,Version=v4.5.1' is being requested from SystemAssemblyService, returning empty TargetFramework

After googing this error I found https://stackoverflow.com/a/38102386/492336, and the solution was to download .NET 4.5.1 and it worked after that!