Some of the incoming mail is forwarded to spam because your e-mail service identifies it as spam. The spam filters try to protect you. Although some e-mails are not spam but have a link or a message attached, the Spam Assassin filter automatically delivers it to the Spam folder. To prevent this from happening with trusted e-mail addresses, simply select these e-mails and choose Not Spam, or move it to the Inbox folder. The service will automatically remember this preference and deliver e-mails of these trusted addresses to their respective folders in future.