Your only real option, if the accountant simply will not respond, would be to sue him to recover the file and obtain compensation for any costs you incur due to his failure to do the work and/or return the materials promptly to you. (For example, if you end up being late filing and incur interest or penalties.O You could alternately try contacting the state board which licenses and oversees accountants, but in my experience they move very slowly and tend to side with the accountant.