First off, I'm on 2017 now, so if this is a known issue and I haven't clued in, feel free to let me know please.

I've inserted a few parts into another part file, and they very obviously overlap, at least an eighth of an inch or more. When I try to combine them into a single body, I get the aforementioned error and it refuses to combine them.

Anybody got any ideas? I'll put a few screen shots up and the part files as well.