The error points out that it is unable to find the excel file. Make sure that the file you are reading (in this case 'file name') is in current working directory or provide the full file path (double check that the path is not absolute and you are using correct case for your file name). If you are getting the same error for CSV files, it most likely is not the issue with xlsread but with the file itself.
Also, I recommend looking through the following discussion to troubleshoot the issue: https://www.mathworks.com/matlabcentral/answers/37872-xlsread-on-mac-os-x
If you continue to face this issue, contact the MathWorks' Technical Support with your excel file:
