A general error occurred while importing sheet gmail from file e:\gmail.xls to sheet 1.
Close the gmail.xls file and try to import.
Even I tried the same I don't have any issues, If the file is open an alert message will be displayed something like file already in use.
The General error occurs the file name else path differs.
The issue what you have listed does not exist, works fine in my machine- stupid comment from the developer