What should I do if The window of the Microsoft Excel Workbook could not be determined appears when using the Designer?

If you encounter an issue where the window of the Microsoft Excel Workbook cannot be determined in Mail & Deploy, it can prevent proper file interactions. Here’s a brief guide to help you troubleshoot and resolve the problem:

Issue: 

When opening a template in an Excel Report, the following error will be shown:

"The window of the Microsoft Excel Workbook could not be determined"

Resolution:

* Close the designer

* In Excel -> File -> Options -> General -> Optimize for compatibility -> Ok (see image below)

* Open the designer