QB Issue Resolution:
QuickBooks Mac uses Apple’s Sync Service APIs for Contact Sync. Unfortunately with Mavericks Apple removed the Sync Service APIs.
Resolution for Issue 'Contact sync settings is grayed out?' available: Yes (Solved).
Source: Intuit Community forum.
Contact sync settings is grayed out?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Apple Sync Service
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Error Recovery for Apple Sync Service [Canada]
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