On the Internet, trust no one. In particular, whenever an unusual and unexpected message appears on your computer, be suspicious of its authenticity.
How can you tell if these messages are phony? What should you do if and when you receive one?
For starters, assume that all such unfamiliar messages are scams. Better safe than sorry. There are no legitimate error messages in internet-connected software that directly link to unrelated third-party sites. If the third-party site requests any personal information, from an email address to a credit card number, be even more suspicious (if that's possible).
Don't click on any links included in such messages. Don't install any software that accompanies the message. Don't provide any personal information at all. In fact, don't do anything that the message requests that you do. Just ignore it and discard it.
Similarly, beware of phishing scams in emails that you receive. If you get an email, even from a website that you frequent (such as Facebook or TradeMe), that includes a link to login to the site: beware! It could be a fake message taking you to a phony site--all designed to trick you into giving scammers your username, password, and/or credit card number.
As a rule, whenever I receive any such messages from known vendors, if I think there is any chance that the message is legitimate, I separately log in to the site, ignoring the provided link. If I truly need to perform the requested action, I should be prompted to do so.
The same rule applies to e-mail attachments. Be especially suspicious of unsolicited attachments from unknown senders.
And if anyone rings you up to tell you that you have a virus in your computer- it will be a scam so hang up.
A Nelson woman gives us a warning in this example http://www.stuff.co.nz/nelson-mail/communities/5183326/Scam-victims-personal-warning
NetBasics site http://www.netbasics.org.nz/
Scam Machine http://www.scammachine.org.nz/#/about
Flash Mob tale gone wrong