From this answer, i am guessing that not only should users archive copies of all their old TurboTax returns (ie, PDFs) but also the working TurboTax documents that generated those tax returns, AND they should keep all their past years' installation CDs so that if they ever need to open a prior year's TurboTax document for the purpose of changing anything, they should reinstall that year's version of TurboTax and only open it with that version. Or maybe keep all years' versions installed, so that the tax tables for each individual year are retained intact. Nothing on the CD packaging explains any of this.
