and checked the add ins and I do not have any
On a mac, xlsread does not use excel to read the file. As explained in the documentation on a mac, xlsread is restricted to basic mode which means it:
- Reads XLS, XLSX, XLSM, XLTX, and XLTM files only.
- Does not support an xlRange input when reading XLS files. In this case, use '' in place of xlRange.
- Does not support function handle inputs.
- Imports all dates as Excel serial date numbers. Excel serial date numbers use a different reference date than MATLAB® date numbers.
You cannot use xlsread to read csv files on a mac. You can use textscan to read the header of your file.
