Dorico can't find Auto Save folders error message

Welcome to the forum, Tom.

The AutoSave location is determined the first time you run Dorico, and that location is then stored in a preferences file (see below). When you copy this file to a new computer or operating system, problems can arise if your user account has a different name, because the location is stored in the preferences file explicitly.

I’ll just quote myself from another time that this one came up: