a hidden object in the hypergraph gets greyed out, and in the outliner it becomes blue
just select it in either one of them and make it not hidden
i attached a screen shot to show you... the sky in this scene was hidden
sorry if its an unwelcome image to your thread
this brings back memories of when i had no idea how to do texture mapping and nothing got named from the default names...
that's a "Ch" pronounced as a "K"
Computer skills I should have:
Objective C, C#, Java, MEL. Python, C++, XML, JavaScript, XSLT, HTML, SQL, CSS, FXScript, Clips, SOAR, ActionScript, OpenGL, DirectX
Maya, XSI, Photoshop, AfterEffects, Motion, Illustrator, Flash, Swift3D