Unfortunately, a credit report isn't a legal document. To release a tax lien requires you to record paperwork from the taxing authorities. Hope this perspective helps!
As Dorothy addressed: unfortunately, the credit report will be insufficient.
There is NO attorney-client privilege based on this interaction. I am NOT your attorney. Further, everything we both just wrote is publicly available on the internet and would be the same as if we were talking in a crowded restaurant. If you need legal assistance use Avvo to find a local attorney in your jurisdiction that you feel can best represent your interests as a zealous advocate. My experience is in corporate tax, white collar criminal defense, partnership tax, and tax controversy/litigation. If you're being audited by the IRS or state taxing authority, or you are taking an unusually risky tax position on a return, that is the kind of thing you should have experienced counsel on your side and we can set up an initial consultation. If you have a family law, debt collection, violent crime sort of issue then I do not handle that. Do not contact me for an initial consultation on non-tax matters.
You can get a release of lien by calling the IRS hotline and asking for the lien department, then provide this paperwork to the credit agency and ask them to remove the derogatory history.