1. Do not let more spammers find your email address
Spammers find your email address using softwares called E-Mail Harvester, its bots that visit websites, extract the email addresses written explicitly in your websites pages and store it in databases to spam you later .. your address will be sold and shared between spammers and more harvester will visit your websites.
so step 1 is to remove any email address explicitly written in your website like in about or contact page, instead, use secure form-to-mail contact form.
2. Enable SpamExperts
3. Enable SpamAssassin
You may mark the incoming emails as 'spam' on the basis of email headers and bodies by using SpamAssassin in cPanel via:
cPanel >> Mail >> SpamAssassin
Then, you can delete them.
For this, you will need to enable SpamAssassin Auto-Delete by clicking on the "enable SpamAssassin Auto-delete" button via cPanel->email->SpamAssassin. Then, set up the score that you want to give. The default is 5. First, it identifies the spam based emails. Next, it increments the spam value each time it gets delivered. When the spam value reaches 6, which is above the set score, the emails will automatically be marked as spam. The spam emails can be discarded by enabling "Spam Auto Delete' in SpamAssassin.
You can also configure SpamAssassin for various checks (blacklisting, whitelisting, email IDs, etc.).
4. Using User-level or Account level filtering.
This is used when you are getting spam emails with common key words, or if the spam originated from a particular email ID.
You can block spams using these keywords by clicking on "create a new filter" tab. Then you can set the filter according to the following examples:
A. Suppose you want to block any email containing the word "watch". The word can be in the email header or body, so select 'Any Header and contains' from the two dropdown menus and enter 'watch' in the blank field. Then, select the action to discard it, or any other option. This filter will block the emails containing the word watch anywhere in the email.
B. For blocking emails sent from an email ID, such as 'firstname.lastname@example.org', select 'From and equals' from the dropdown menu and enter 'email@example.com' in the blank field, with the appropriate action.
C. For blocking emails that have keywords like "watch" "watches" "Watches" WaTches" etc., select 'Any Header and matches regex options' from the dropdown menu and write the appropriate regular expression in the blank field.