Dialog boxes can display error messages and warnings with a text tile known as an error tile (errtile), or with a nested alert box. The following guidelines apply to both:

• Error messages should be complete sentences, punctuated as such, with an initial capital and a period at the end.
• Error messages should explain clearly the problem or potential problem.
• After reporting the error, shift the dialog box's focus to the tile that triggered the error, if possible.