Connected means SyncNow knows of no problem; Offline means the FTP connection is failing or the server cannot be reached; Authentication required means the credentials are missing or were rejected, for example FTP sign-in rejected; Not configured means the project has no hosting connection yet. When the owner has revoked your access, the state is Access revoked.
The state follows every FTP operation that goes through SyncNow on that PC, including the agents' work, and while the app is open a project nobody is working on is checked about every 30 minutes (every 10 while a problem is open) with a check that only reads. In the Projects list a yellow sign replaces the icon of a project with a problem, and clicking it explains the reason. A failing database and writes paused by the hosting are not connection states: the yellow sign on the project's row shows them, and while SyncNow's FTP connections to the hosting are refused or paused the Overview says Hosting connection is failing under NEEDS YOUR ATTENTION.
Fix Authentication required or Not configured in the Connections tab: Edit on the Hosting card opens the server, user and password (a password SyncNow already holds shows as Stored securely, with Replace), Test connection tries them, and Save hosting connection tests them again before saving. A database is fixed from its own row on the same page. The state returns to Connected by itself as soon as a connection succeeds again; if your access was revoked (Access revoked on the project's row), only the owner can invite you again.