I created a custom profile (to use as a form on my website) with a custom file field...When the user fills out the form, they upload a file, and the form is sent to the admin email address. When I open the email and download the attached file, I am unable to open it; the file becomes corrupt. However, if I use FTP and navigate to ".../files/civicrm/custom" and download the file from there, the file opens and is not corrupt.

The website is using wordpress.

Any help is much appreciated. Thanks in advance.