ok i know this may sound silly but is it for modelling or used in a scene? Make sure you have no lights near it.

I did this before. I was creating a nice sunset ocean scene, and my point lights etc. was effecting my plane. Be sure its on default lighting.

Secondly, assign a material to it, pref a lambert. You might be trying to add an image plane, without assigning a specific material to it and it could be effecting your scene.

3rdly, (again, i know this is a silly question), but have you tried turning the image plane around in case its on the other side. lol ...you never know.


Failing that its either a gliche or something out of my hands.

good luck