You cannot attach an executable file like a normal file.  Gmail will display the error message –  “FILE is an executable file. For security reasons, Gmail does not allow you to send this type of file”.
To overcome this issue, do the following as a sender of the email.
  • Rename the file without an exe extension,
  • Compress it with any compression utility and then attach it.
Now it will get attached, and uploaded successfully. The receiver of the email should uncompress the attachment and rename it again with exe extension.