Identity Protection Personal Identification Number, or IP PIN, is a single-use identification number issued by the IRS to a taxpayer who has previously been the victim of identity theft. The IP PIN is used to protect the taxpayer by preventing their tax account from being used by anybody else. The IP PIN will be required to file your return to authenticate your identity.
Read page 7 of Pub 4012 (2012 version) for more information. TaxWise Input is near the bottom of the Main Information Sheet.