Strange normal map behavior in viewport

My normal map is looking odd after closing and reopening my blend file. It looks fine when I first apply the material, but after closing, it comes back looking like this (right side).

If I delete the material and reapply the normal map it looks fine, but again, it messes up after reopening the file.

Why no blend file and normal map supplied ?

Sorry. Actually I seem to have stumbled onto the reason, it was only doing this while using a 16-bit tiff. When I converted it to 8-bit it looked fine again.