Had a somewhat similar situation where I Proformd my clients to 2020 from Lacerte 2019, but when I opened 2020, only the individual clients would show up, no corporate. I downloaded 2020 Lacerte one more time and updated both 2019 and 2020 software's before proceeding to Proforma again. At this point when I opened Lacerte 2020, all the clients were there. Hope it helps!