About 42% of senior managers in a new OfficeTeam poll cited “Not asking for help” as the No. 1 networking mistake in a new survey by staffing firm OfficeTeam.

“Some people still feel embarrassed about being out of work, or they are shy about ‘inconveniencing’ others,” says Robert Hosking, OfficeTeam’s executive director. “But connections are more important now than ever, and every one counts.”

It might help to bear in mind that most of those connections are genuinely glad to help if they can. “Not providing help when others need it” came in near the bottom on executives’ list of networking errors, mentioned by just 7% of them.

Almost one-third (28%) said that “not keeping in touch” is the networking mistake they see most often. Says Hosking, “Follow up with people you meet immediately after an event, while the connection is still fresh.”

Then drop an email or pick up the phone every now and then, and respond promptly to any requests that come your way, he adds. Don’t forget to say thanks: almost one in five (17%) executives said “not thanking people for their help” is a networking no-no they frequently see.

The biggest surprise in the OfficeTeam poll, and one that sites like LinkedIn, in particular, should appreciate: although the conventional wisdom says meeting people in person is far better than online, 47% of these respondents chose networking in cyberspace as most effective, while fewer than half as many (24%) picked “meeting in person over lunch or coffee.” Networking events got only 13% of the vote.

And, at least according to this poll, don’t bother taking up golf, tennis, or model trains as a networking strategy. A tiny 2% of executives thought that “personal interest activities (sports, hobbies, etc.)” will get you anywhere.

So why is it more effective to meet people online than in person? “Technology has made it quick and easy to stay in touch with people from just about anywhere and at any time,” Hosking notes. Even so, he has his doubts. “Face-to-face meetings can build rapport in a way that electronic communication can’t. You get to put a face to a name and make a memorable first impression,” he says. “Connecting in person takes more time and effort, but can deliver much more value.”

The solution: do lots of both. “You can make acquaintances through in-person meetings, and then nurture those connections online.”

Laid off, quitting your job, or changing careers? Be careful what you say to, or about, your old boss. About 6% of the executives in the survey called “burning bridges with past employers” the biggest networking mistake of all.