Steve got a copy of Sophos antivirus, but it suddenly stopped working after installing Windows 10. Leo says that's because sometimes security software can cause problems with upgrading, and that sounds like what happened. Leo also says that the version of antivirus may also be the issue here. But Leo says that times have changed and he doesn't really recommend antivirus software anymore. Most security experts don't use them. Here are some tips for staying secure online:
1. Keep the computer, browser, and any other software that goes online updated.
2. Be very cautious about installing software from unknown sources. Only get software from very reliable first party sources.
3. Watch out for scams. Don't trust popups that claim to be from a legit source trying to update or install something.
4. Watch out for phishing scams. Don't trust messages with links to click, even if it looks very legitimate.
Microsoft has it's own antivirus now that's better anyway, called "Microsoft Security Essentials" for Windows 7 and "Windows Defender" in Windows 10.