Hi, The ABC marker is a good indictor to have, BUT if you desire to remove it...go to: Tools>Option>Select Wizards and Tips in left pane > Deselect "Show In-place warning markers".
That should do it. Again, although a nuisance, this little critter can be helpful since you may not always see the red wavy line indicator that lets you know something is misspelled (i.e. values in a drop-down list, text written in a validation pattern message, etc.)
Shaun