How to avoid fatal mistakes in cover letters?

In both cover letters and resumes, there are fatal mistakes that can cost you. Mistakes in a cover letter can sometimes be more tragic as the cover letter is often the first document that an employer reads during the hiring process. Errors in spelling, accidental typos, and problems with grammar or punctuation can earn your application a trip to the trash can. Proofreading your document several times and even having another person look over it after you have done so is an excellent way to catch errors before they ever reach the wrong set of eyes.