REGENERATION PARTS

Hi, in an assembly "A" I have a lot of this parts "B" (lets say 100). When I modify another subassembly "C" (or parts "D") of the assembly "A", It takes a lot of time to regenerate the 3D model "A", and in the left bottom of the screen it plot these messages

"Relations have errors/warnings. Refer to the message log for the details or visit relation UI.

A - assembly A - regeneration completed with 94 suppressed feature(s) or component(s).

Part 'B' not changed since last regen".

I think it is a tentative to regenerate parts that are not in checkout and takes a lot of time to do this tentative.

How can I fix this problem?

Thank you in advanced.

Michele Barile