'Operation Failed' when trying to enable Zoho CRM in Zoho SalesIQ

'Operation Failed' when trying to enable Zoho CRM in Zoho SalesIQ

Hi there - I am Administrator for both and when trying to enable Zoho CRM in Zoho SalesIQ I am getting 'Operation Failed' message.  I am newish to Zoho and inspired following the Zoholics Sydney this week.  Thank you in advance.  Sue.