After you have evaluated the mesh using visual inspection, mesh statistics and mesh diagnostics, you need to fix the identified problems in order to have a clean model before you run an analysis.
To fix mesh problems, you can use the Mesh Repair Wizard which runs a series of diagnostics on your model and, for each diagnostic, allows you to fix any problems detected.
Alternatively, you can use the mesh repair tools to fix any problems you have identified from the mesh statistics report.