QB Issue Resolution:
Type command-F to bring up the Find window. Enter an amount from one of the checks you can’t find and search for it. Double click on it when it is found and it will open in the check window.
Resolution for Issue 'How to find a Check?' available: Yes (Solved).
Source: Intuit Community forum.
How to find a Check?: 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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