The Better Business Bureau says an increasing amount of tech support scams are being reported to their agency. There are two versions currently in circulation. In one version of the scam, a pop-up suddenly appears on your computer screen with an ominous warning from a well-known tech support company.

The pop-up will ask you to call a number to resolve the issue. When you call, BBB Investigator Don O’Brien says a “technician” will tell you your IP address is being used by shady individuals.

In a second version of the scam, you simply receive a call out of the blue from someone making similar claims. He says you should never open attachments or links in emails from unknown senders; be wary of unsolicited calls; and never give strangers remote access to your computer.