Hi @Mac User,
This issue seems to be caused by the 3rd party add-in. Please refer to the solution in this thread: https://answers.microsoft.com/en-us/msoffice/forum/all/run-time-error-53-file-not-found-after-installing/ae91a2f3-4447-4575-a4e5-8f5090747bd9 and try resolving this issue by John Korchok's answer.
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