How do l get musty odors out of old cupboards?

First, I would give them a good cleaning with Murphy's Oil Soap. You can also clean the inside with a mild bleach solution. Place a bowl with baking soda or coffee grounds in the cupboards. They are great for absorbing odors.

Wash down with vinegar, soap and water. Dry. Lay down a layer of kitty litter on shelves, close up for a week. Clean out.

Newspaper with coffee beans. :) Leave in for a couple of days.

After washing them out as described above, I would leave them open for awhile. You could also leave a box of baking soda in there for awhile to absorb odors.