I have been unable to connect to the P6 database and have tried everything possible for the API for version 7 (no longer listed on the downloads page) to work. I was curious if this is because they are no longer compatible.
Theoretically yes, Synchro 2017 is compatible with P6 v7, but the old SQL DBs compatible with P6 v7 cannot be installed under Windows 10.
If you are having trouble installing the API, we recommend using P6 XML files to exchange data with Synchro. Simply export the schedule from P6 as an XML, then import to Synchro via File>Import>Primavera P6: choose File for Data Source. In Synchro P6 XML files can be imported, exported, and synchronised from/to