A hoax is a message, typically distributed via e-mail or newsgroups, that is written to deliberately spread fear, uncertainty and doubt. Hoaxes prey on the lack of technical knowledge and goodwill of all those that receive the hoax. Generally, hoaxes are warnings about threats to your computer that do not actually exist.
The most common type of hoax warns one to not to open an e-mail message with a certain subject because it will activate a virus. Opening an email can not activate a virus. Reading an email does not involve the execution of any sort of programs, which is a prerequisite for a virus to activate. The only exception to this is if your email software is configured to automatically open attachments. Most hoaxes ask you to forward the warning on to as many people as possible. This is how the hoax spreads itself. As a general rule, if you receive any message that asks you to forward it to others, you should check the accuracy of the message first. If a message warns you about a virus and doesn’t have a link to a source that you can trust (anti-virus companies or well known software companies) then it is most likely an hoax. If you still might think that the warning is true, do some internet research to check if the warning is legitimate. Do not just forward the e-mail. Passing on messages about these hoaxes only serves to further propagate them.
You can find out if your message is a virus hoax by following this link: https://www.sophos.com/en-us/threat-center/threat-analyses/hoaxes.aspx