What’s the meaning of this window??

[marker4x4]

When processing Surface Seq., sometimes the Surface Side window pops-up (see attached JPG).
I'm not too sure what's the meaning of that? I just click DONE and keep going...
Is that important at all?
BTW, the model is imported, but my Milling Surf. (highlighted red) is made in ProE.

Thanks for any input.


View attachment 3099

 

[pronc]

I might be wrong but check your import surfaces. They are probably not point to the same direction. I ran into this when imported some catia surface for machining. You might have problem with the tool not even touches some of those surfaces not pointing the same direction.