QB Issue Resolution:
The trial version cannot be registered. You can download the 2011 release version and register that. Its on Intuit’s web site under support when you get to the QuickBooks Mac section.
Resolution for Issue 'Why can’t I register my trial version of quick book for mac 2011?' available: Yes (Solved).
Source: Intuit Community forum.
Why can’t I register my trial version of quick book for mac 2011?: 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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