Tips for safely using e‑mail and the web
Use caution when opening e‑mail attachments. E‑mail attachments (files attached to e‑mail messages) are a primary source of virus infection. Never open an attachment from someone you don't know. If you know the sender but were not expecting an attachment, verify that the sender actually sent the attachment before you open it.
Guard your personal information carefully. If a website asks for a credit card number, bank information, or other personal information, make sure you trust the website and verify that its transaction system is secure.
Be careful when clicking hyperlinks in e‑mail messages. Hyperlinks (links that open websites when you click them) are often used as part of phishing and spyware scams, but they can also transmit viruses. Only click links in e‑mail messages that you trust.
Only install add-ons from websites that you trust. Web browser add-ons allow webpages to display things like toolbars, stock tickers, video, and animation. However, add-ons can also install spyware or other malicious software. If a website asks you to install an add-on, make sure that you trust it before doing so.