A problem arose in a workflow that uses a Dynamic Input tool used to input a list of files contained in rows of an Excel file where a file with an .xls extension is not being input when many others with the .xlsx file are being input just fine. During trouble-shooting, an exact copy was made of the .xlsx file that contained the list of the files to input but instead it was saved with an .xls file extension. This was done to create a different Dynamic Input tool that could be configured with the .xls extension.
The Excel files holds file names and paths that are to be input by the Dynamic Input tool and with certainty the worksheet names and paths are all correctly referenced. The Dynamic Input tool configured with a format using .xlsx files finds both the file paths and the worksheets when the file input has an .xlsx file extension. Whereas the one configured using the format .xls finds only the files path and not the worksheet resulting in an error saying:
Error: Dynamic Input (49): Error opening table: Microsoft Access Database Engine: The Microsoft Access database engine could not find the object 'Worksheet Name'. Make sure the object exists and that you spell its name correctly. If 'Worksheet Name' is not a local object, check your network connection or contact the server administrator.
A logical solution would be to simply save the file to be input that has an .xls file extension as a file with the extension .xlsx. That is, if the file was able to altered in anyway and of course in this case it is not. Why does the .xls extension engage the Microsoft Access database engine in a different way than the .xlsx extension does?