The term graymail refers to solicited bulk email messages that are not spam. Email that falls under this term may be mistaken as spam since content may be similar to most spammed email messages that a regular email reader sees – it can sell a product, it may be about shopping or coupons, it may also be notifications of newsletter content, or social networking sites’ updates. Graymail messages are likely to be reported as spam also because of its frequency. Legitimate newsletters that we opted in at one time or another may come in on a daily or weekly basis. Graymail is not malicious.
Trend Micro products detect marketing newsletters and social networking updates as graymail. Note that while Trend Micro products detect these kinds of email messages, these messages are not tagged as spam.