What happens if my husband was driving without a license which violated his probation?

Your husband could face a range of penalties from court costs to incarceration. A major factor in determining his results will be the nature of the underlying offense, for which he is on probation for and the original sentence. Other factors to consider are how many prior violations have occurred, his relationship with his probation officer and the judge before whom he has to appear. I would advise you to contact an experienced criminal defense attorney.