QB Issue Resolution:
Once a new OS comes out generally that’s the only one available through the App Store. I suspect you’ll have to contact Apple support for anything else.
Resolution for Issue 'How can I update my Mac os x10.6.8 to>10.7.3 or greater?' available: Yes (Solved).
Source: Intuit Community forum.
How can I update my Mac os x10.6.8 to>10.7.3 or greater?: 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 Quickbooks
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