I have some friends in my contacts who are not very familiar with Komputerz. Apparently they have some kind of malware on their laptops that occasionally sends spam by their email address.
I am using Gmail and my friends are using different services (including Gmail and Yahoo! Mail).
Should I mark these emails as spam? Specifically, I just want to help Gmail to recognize these kind of emails as spam, but I don't want to make Gmail think my friends are spammers.
Best Answer
Spam filters generally work against the content of the message.
In fact, given that spammers like to forge their From: headers and that, historically, there was no way to automatically validate the message's origin, most spam filters I'm familiar with don't really care about the From: address.
Despite being a GMail user myself, I'm not 100% sure about their implementation, but my advice is to just mark away. It's what I'd do in your situation.