Are you here because you've received an unsolicited email - spam or an email with a virus attached - that looks like it came from us?
Spammers, email scammers and virus writers can forge an email address to hide the origin of a message. Spammers generally use any address which ensures that returned mail and complaints won't come back to them. Scammers usually use addresses that attempt to fool users into believing that an email is from a legitimate source, such as your bank.
Virus writers can use both techniques, propagating viruses by emails that appear to come from official technical support sources (such as your ISP, or Microsoft) or from friends and colleagues of the recipient. Viruses often harvest both real target addresses and fake sender addresses from computer address books like the ones used by email software. If someone you know gets a virus like this, then it may send a copy of itself to you - or it might take your address from your friend's address book and send copies of itself to other people, addressed as if they were FROM you.
If you have received spam or virus email that looks as if it's from us it's very unlikely that it actually is.