Remove all the papers and files from the cabinet before you begin cleaning it. This prevents papers from being damaged.
Use a scrubbing pad or sandpaper to scrub away the rust stains. Use force on the stubborn stains. Apply a little mineral oil to tough rust stains with a paper towel. Let the oil soak in for five to 10 minutes. Then scrub the area again with the scrubbing pad. Wipe clean and dry.
Use a paper towel to apply white vinegar to the rust stains. Let the vinegar soak in for five to 20 minutes, depending on the amount of rust to be cleaned. Scrub with the scrubbing pad. Wipe clean and dry. Repeat if necessary. The acid in the white vinegar helps to remove the rust.
Make a mixture of one part lemon juice and two parts borax in a small bowl. Apply the paste to the rust stains with a paper towel or scrubbing pad, Wait 10 to 20 minutes for the paste to settle into the rust. Scrub with the scrubbing pad. Wipe clean and dry. The acid in the lemon juice and the abrasive action of the borax work together to break down the rust.
Place all of the papers back into the rust-free file cabinet.