It is always tough to accept mistakes but Becky Roberts has dared to jot down her most appalling professional mistakes, along with the painful but invaluable lessons learned - Confessions of an IT pro
Her confessions include deleting important files, going live on a trial software, taking backups for granted and ignoring the free training programs. Interesting read.
My most embarrasing moment during the job was when I accidently sent a personal email to the entire global staff because my friend's name was similar to the "all staff" email alias.