Despite prominent how-to posts on how to add datasets to Azure Machine Learning that say Excel is supported, when I actually go to add a dataset and select a local Excel file, there's no option for "Excel" in the required datatype property dropdown. I'm surprised that Azure wouldn't support Excel (right?) - am I missing something?
The dropdown list indicates the "Destination" datatype for the new DATASET file you are creating, not the source type.
I just uploaded a .xlsx file successfully into a .CSV file in AML.