How to quickly delete all spam email permanently Accounts frequently fill up with tens of thousands of spam messages at which point deleting mails one by one is no longer feasible. The best way to delete the spam, if you have access to your main FTP account is to log into the server and change to your email directory. i.e. /mail/[domain]/[email account] within your home folder. Here there will be a file called "spam" which is your spam folder. Just delete the file and all the spam will be gone from WebMail.