Symptom
When you try to import a .xls file, you see “Failed to open /xxx.xls” error message like below.
Workaround
Open it with Excel and save it as “.xlsx”
On Excel’s Save As Dialog, select “Script Open XML Spreadsheet (.xlsx)” like below.
Go to Exploratory and select “.xlsx” file instead of “.xls” file. Then you might be able to import the file.
