I recently answered a similar question. I would like to direct you to that response, as the steps will help in your current situation as well.
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Error 15242 occurs when the payroll or QuickBooks update did not complete successfully. […]
Resolution for 'choose Employees issue: 'Where do I find quickbooks pro 2013 product updates' available: Yes.
The choose Employees 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 choose Employees issue yourself by looking for a resolution described in the article. If it is a complex choose Employees issue or you are unable to solve the issue, you may contact us by clicking here or by using other choose Employees support options.
For more information about resolving issues related to choose Employees in Quickbooks/QBO or to get support for the issue 'Where do I find quickbooks pro 2013 product updates', click the link below: