Cycles fails to render materials

Hi all, I’m having a very strange problem with the materials that I try to render out. I’ve copied and pasted from the original project, and it carried the issue over. I’m using an old computer, Nvidia G600, but it happens with the CPU also.

All my materials and textures have been working just fine, but then randomly, everything is rendered out black. I’ve checked nodes, and I might have missed something but everything looks like it should be in working order. I’ve googled but can’t find a solution.

When viewed in material and texture mode, everything looks fine, it simple won’t render. I’ve attached some screen shots and will post more if needed. Please help, there have been so many\ issues already and everyone has been resolved except for this major one.

Those screenshots don’t show the necessary information for us to find what possibly is going wrong. Please upload a blend file that shows the issue.