I found a solution that seems to works – Switch to multi-user mode (This is done from the File menu and follow the prompts) then switch back to -Single user mode..
Resolution for '12 kb issue: 'Why does Automatic Backup fail and only creates a 12kb temp file when you “X” out of QB ?' available: Yes.
The 12 kb 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 12 kb issue yourself by looking for a resolution described in the article. If it is a complex 12 kb issue or you are unable to solve the issue, you may contact us by clicking here or by using other 12 kb support options.
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