Typically we were able to get those reduced to a "Letter of Warning" which is less severe than a Letter of Correction. The difference being is that there was no determination of an error, but rather a reminder (warning) not to make an error.

I'm sure the involved party knows the difference and would not make it look worse than it really was by using the wrong term.

Folks have gotten interviewed and hired with past Letters of Warning. As others have written, honesty is always the best policy. Even if the FAA does not have the letter on file, it will survive for eternity in the employer's personnel file and get picked up during a PRIA request.

Another tip ... if a person has a letter that will get picked up in a PRIA request, it is fine to add a letter from the Pilot explaining the circumstances and correcting anything the employer got wrong. In some cases that helps mitigate an ugly letter and since it be sent in the same package as the PRIA response it looks official.