HFSS errors and their solutions

Lately I have been constructing som passive microwave components using Ansoft HFSS. It is a very powerful piece of software, but somethings the error messages can be very hard to interpret. So this post will be continuously updated with problems I have had and solved.

1. This error I believe is related to meshing issues. However, I could only reproduce it in a statistics analysis where it reoccurred until I changed the mean in the distributions: [error] Critical features could not be preserved correctly. (10:14:21 AM  Aug 22, 2016)    [error] Statistical Analysis failed - Solver error. More information may be available in...
2.