I Can't make the UI button work in any way!

I can’t make the canvas and any of his features work in runtime. To be more specific and clear about whats hapen. I decide to create a working Main Menu and Pause Menu, so i started to read the documentation about that feature of unity. After that i create the first layer of the main menu, and i hit play. Everything work fin that moment, then i start to create the second layer and scripting everything. After that i can’t make the canvas work in any of his features.

The ui buttons notworkin, sliders same. So i decide to take the bull by the horns, as we say in spanish. And i create a new proyect without any asset in it, and i create a simple button from the create GameObject menu. It work properly in detect “OnMauseOver”, “OnClick” and so on. But then i stop the scene and ReStart it, and there is the problem again. This is frustrating.

I have Unity 5.1.4f1(32bit) personal version, i can’t upgrade it for now becouse i still have my computer with Win Xp, may be is somthing about the version i dont know. Is not the way i create the ui, becouse even when i create from GameObject Menu, give me this trouble.

Are you getting any errors? when start creating UI elements?
Are you trying to create button in runtime?

Post the error logs here.