Guilin Sun
Ansys Employee

We are not allowed to download files in this forum. But I had a look. I did not find anything significantly wrong. However since you did not mention how do you set the angles, it is hard to comment.

Current you use polygons. You will need to have the angle in model or in structure group to sweep/optimize it.

You may also try to use mesh accuracy 2, but with override mesh for the max title angle region, and try again.

Error code 5  is a system error, probably from c++ library. You can search online for that error message.