face where the face normal differs substantially from the vertex normals

"Mesh has 1 face where the face normal differs substantially from the vertex normals.
Although this does not necessarily mean that the mesh is bad,
these normals can cause problems if the ultimate goal is for rendering or boolean purposes."

Thats the message I get from the check. I have googled it a bit but nothing seems to work with me. Is there any standard methodology which can cure these cases?

Thanks