This topic went unanswered in 2016. I am looking for a solution other than unprotect the sheets. I am posting this question in MS Office forum as well since I don't know where the issue lies. I have a Nintex 2013 workflow that is using Query Excel Services action to read certain cells in an Excel file and store the value in a variable. Everything worked great during test until the owner of the Excel template protected the sheets so users' couldn't overwrite any formulas. After that, I kept receiving "Error querying Excel Services. We're sorry, we couldn't open your workbook" error on my Nintex workflow. Is there a way to use Excel Query Services against protected cells with formulas? Maybe grant access in the Excel template to the farm credentials used in the query? My query control is setup as follows:
