Thanks for posting your question in the Microsoft Q&A forum.
It seems that the issue is related to a temporary file path or directory that Excel is trying to access or create during the "Send Workbook" process.
Sometimes, closing and reopening Excel can resolve temporary file or directory issues.
Ensure that you have the necessary permissions to create and write files in the temporary directory mentioned in the error message
Try clearing the temporary files and caches for Microsoft Office applications.
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