I seem to be having issues with fillets.  Running 2016 SP 4.0.

If you care to open the attached part, I'm trying to put a R.015" fillet on the red faces (the perimeter edges of said faces, rather).

I keep getting this error:

The "complexity" really doesn't look to be all that much. 

I tried one edge at a time, same error.

I tried a face fillet, that didn't seem to work at all.

Any ideas?  Thanks.