A few tis:
- Do not use firstname.lastname@example.org address to register for newsletters/action etcetera. You could forward mails from email@example.com to firstname.lastname@example.org if you want to use info@ so badly.
- Activate the spamfilter through your hostingpanel or increase the level of the spamfilter by decreasing the score and by activating "adult list".
- Make use of mailforms instead of links with mailto: in it.
If this doesn't help, we could help you with an extra spamfilter, which reduces the chance of spam/virusmails.
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