You can block an e-mail using or redirect mail using filters. There are several uses for using e-mail filters, but one particularly useful one is the filtering of spam e-mail Spam is the electronic version of junk mail, and has been around since the Internet was created. E-mail filters are a way of filtering your e-mail to remove unwanted mail based on a variety of criteria. You can block any sort of e-mail, not just mail of a commercial nature. Blocked mail can be deleted automatically or sent to another e-mail address or script. Some clients use filters to redirect mail that may come from a particular address. These filters are quite flexible in how you wish to use them.