>Yes. 4.5 replaces 4.0. There may be some subtle differences.

As per listed, I have in the Program Files:

Microsoft .NET Framework 4 Multi-Targeting Pack
Microsoft .NET Framework 4.5
Microsoft .NET Framework 4.5 Multi-Targeting Pack
Microsoft .NET Framework 4.5 SDK

This seems to indicate that the runtime 4.5 is installed. And, this is the latest vesrion: 4.5.50709. Is there another 4.5 related item I need to download to benefit of the runtime or this is it?

VS 2012 did the job to install the 4.5 related items. But, it seems it removed the 4.0 runtime. The registry HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.0\Client indicates that Version is 4.0.0.0. So, it is trying to run the runtime of 4.0.0.0. If VS 2012 removed that runtime, that might explain why I have this situation.

Now, the question is why do I have this situation? VS 2012 installation should have done everything accordingly to what it needs to run an application. Next, would be to know what I should do to resolve the issue.