Why does my normals map flip?

I made a normals map from a muiltres sculpt and when I’m in blender render with normals clicked under image sampling, everything looks fine. The seams line up. But when I’m in Cycles the seams are reversed. The front half is correct, but the back seams are reversed it seems or something I don’t understand is going on. What is causing this?

It’s caused by Cycles material setup/assignment, UV maps, geometry, view settings, model import/custom normals, blender version(s)/user preferences for those, post-processing setup, modifiers, or any combination of those.

wow that is a lot lol.

And that wasn’t even all of it. Your cropped screenshots don’t provide any of that information and aren’t enough to verify the workflow for what you said you did, so much more information is needed for someone to help figuring it out without randomly guessing. Easiest to share most of that information is with a .blend file. Instructions on how to prepare the file and upload linked in my signature.

I figured it out. I didn’t add a vector/normals map node. I had the imaged texture straight to the material output.

Every time I fix one problem and new one arises it seems. I have all my textures and normal maps finished. I went to join the model and the mode turns black. The model is broken up into (head,arms,chest,legs) (belt) (trunks) (claws). After I join the model all the color textures are ok except for the body mesh. If I go to edit mode and show the uvs, all are showing except for the body. So for some reason when I join the body UVs are gone but the others show. All my textures have original names and my normals are fine.