@CMSERVICE  That's efiling.

Refunds for 2014-2016 are lost.

All prior year returns can be filed. 2014 - 2017 on paper. What's client's reason for not filing and for coming forward now?

Get a large retainer.

EDIT: Just reread and saw you said 2004, not 2014. Go to irs.gov and look up nonfiler. Generally IRS only wants 6 years returns filed to get the taxpayer back into the good graces of the system.