If you're thinking about grabbing some performance boosting software, check it out before you download. Do a little research, such as looking for reviews or recommendations on sites like this one.
Second, never believe a website that says your PC is having problems. If you're concerned your PC may have an issue or some new program you don't recognize says you have a problem, get it checked out in person.
If you live near a Microsoft Store, try the retailer's Genius Bar-like service called Answer Desk that will check out your PC for free. Otherwise your local PC repair shop can help, and paying a legitimate service provider is a lot cheaper than paying a scammer. Of course, asking a geeky pal for help is always an option, too.
Finally, keep in mind that these kind of scams have grown beyond PCs. In January, security firm Malwarebytes discovered a tech support scam targeting mobile devices. In those cases, the call centers were cold-calling prospective victims posing as tech support specialists responding to supposed problems. Similar scams try to entrap users with unsolicited email.
If you receive a cold call or an unsolicited email regarding tech support, do not respond. Just hang up the phone! More importantly, no matter how convincing they seem do not hand over personal information such as your name, address, or payment information.
As with most scams, as long as you keep your wits about you and use common sense online, you'll be fine.
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