Cannot compile, LINK error

Hi, I’m new to C++ and UE4, and after following the programming tutorials I hit this brick wall, an error that I have no clue what it says, something about being unable to link:

Any ideas what could be going on?, could this be related to the problem I have when I try to debug?, however in this case I just building the solution.

Thanks.

As posted in the following forum thread: Cannot compile, LINK errors?. - C++ - Unreal Engine Forums

You had the editor open while building your project, hot reload feature is available in 4.5 or higher.

Cheers,
Moss