Only one account is present (old firm.)  I think I need to approach Lacerte from a new angle.

Let's say I had a stand alone Lacerte account with firm A.  On the 1st of January  I moved my entire practice to firm B.  Firm B also uses Lacerte.  I need to integrate these prior year Lacerte files with firm B, i.e. need Lacerte to change the firm info from firm A to firm B on all prior years.  Maybe then firm B Lacerte will download onto my computer correctly.  Sound reasonable?