Cannot connect to Fruux
Fruux requires an app-specific password to be used with 3rd party apps instead of your original login and password. Log into www.fruux.com and then click on "Setup Syncing", there click on BusyContacts or BusyCal and create an app specific username and password. Use that to login.
Please note, when syncing BusyContacts with Fruux for the first time, you need to log into www.fruux.com, click on Contacts and then click on Add a new address book in case you see a You don't have an address book notice. Without at least one address book, BusyContacts won't be able to sync.
UPDATE: As of July 2020, Fruux servers have introduced a bug where it would either return malformed responses to requests or would fail to process requests of a certain size. This bug has not been fixed (last checked Jan 2022) and affects everyone. Fruux customer care has not responded to complaints. Unfortunately we would not recommend using Fruux. Instead please explore many of the other popular services out there: iCloud / Google / Fastmail and so on.
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