You probably know this type of person: After the briefest of encounters--or no encounter at all--he sends you a Facebook or LinkedIn request. Do you connect with him even though he's basically a stranger?

Savvy networkers say you shouldn't connect with people you don't actually know. And that's the policy Matt Haughey, a blogger and founder of the gas-mileage tracking site Fuelly, typically follows. Until he became that person by accident.

After receiving an invite to connect with an old friend and colleague via LinkedIn, Haughey logged in to his under-used account and wondered: Who else had he missed in assembling his online professional network?

Conveniently, a pop-up appeared with recommendations taken from his Gmail account of people he might know and want to connect with. Haughey deselected a few strangers from what looked like a short list of people, and proceeded to invite one or two people to his network. Or so he thought.

Haughey quickly realized that he had, unwittingly, invited virtually his entire contact library--minus the four or five people he had deselected on the first page--to join his network on LinkedIn, including many outdated acquaintances and others whom he had no interest in contacting.

“I got one message from a person I had banned [from my website] saying, ‘Oh, you want to connect, but you don’t want me on your website,’” Haughey says. He also received an unwelcome message from an insurance salesman with whom he had once shared a back-and-forth conversation that was “not joyful.”

Apparently, the error is a familiar one: Haughey’s experience caught the attention of many sympathizers. After describing the experience in detail on his blog, Haughey received dozens of comments from readers.

“I did the exact same thing,” wrote one follower, “It's terrifically sneaky. It was really not clear that it was going to email everyone else in the list... It emailed anyone I'd ever interacted with, since 2007. Very, very embarrassing.”

“Embarrassing” and “annoying” are two words that Haughey also used to describe his experience. As an infrequent user of LinkedIn, he views invitations from people that he’s barely met as pushy and uncomfortable.

But perhaps this kind of cyber cold call is not as strange as it used to be. Three hundred people--mostly strangers, in Haughey’s mind--accepted his invitation immediately. Two even called him, attempting to make in-person connections after the invite.

The accidental spamming also initiated some conversations between Haughey and his followers.

“Hey Matt,” one reader wrote in response to Haughey’s post, “I got your request last week and was totally perplexed! But honored, since I've been a long time fan and was surprised to see you request a connection. I guess we must have emailed years and years ago.”

“Yeah, looking at my email, it looks like we exchanged email... back in 2004. Cool to see where you work now, I'm a big fan,” Haughey replied.

Another one of his readers claimed to have received a job as the result of an accidental LinkedIn request.

“I guess if you bother someone at the right place at the right time it might land you a job,” Haughey concedes.

But a spammer is still a spammer.

If a stranger had reached out to him on LinkedIn and asked for a job, he would not have been very likely to hire them.

“There is almost zero chance that I would be interested in that,” he says.