The following error usually means that the Google API OAuth token that Yoxel holds is not valid anymore and a connection to Google Contacts or GMail IMAP/SMTP is denied. This happens when you've changed/updated your Google password, the token that Yoxel Portal holds got invalidated.
Google (CONTACTS): No OAuth token to access calendar API.
No OAuth2 token to access calendar API.
The solution is to re-authorize Google access in Yoxel:
- Open the Google/GMail service, make the contacts/email sync inactive, save
- Open again, make the contacts/email sync active, save