Act! user licences are sold on a named user basis – each
individual user of the software requires a licence to be able to use it. Act! can be shared on a read only basis basis with the requirement to purchase a paid licence.
In order to share a database using Act! Pro or Act! Premium
for Windows with multiple users a network connection is required.
Check the official Act! system requirements
Office 2019 Support: Please note, that while Office 2019 is supported with Act! v21, due to the timing of the release final certification has not been completed against it.
Certification is targeted for v21.1