By Larry Buhl, for Yahoo! HotJobs

Most professionals are aware of the value of networking for career advancement. Appropriate career networking can lead to opportunities that are hard to acquire on your own. But there is such a thing as bad networking -- and that can do some serious damage.

Career experts point to several common networking pitfalls and how to overcome them:

Problem: Homogeneity

If you're interacting only with people who do exactly what you do or who work at the same company -- or who are all out of work -- they are less likely to help you reach the next rung. If you're all looking for jobs, you may spend your time griping rather than sharing information. And if they see you as competition, they may even actively work against you.

Solution: Expand Your Circle

"You should be looking for diversity on all levels within your network," says Barbara Safani, president of Career Solvers. "Take a look at who's in your network in terms of job titles, age differences, geography and even ethnicity. Start leveraging the people you know well in your circle, and find out who else they know who may be different from you."

Problem: Desperation

Many professionals start networking when they're out of a job. This leads to the (often accurate) perception that you want one thing and aren't likely to offer anything in return. Your contact may help you out, but it may be the only time. Worse, you may acquire a reputation as a taker and not a giver. "If you start your network with an open hand, it's too late," says Heather Hamilton, staffing manager at Microsoft.

Solution: Reach Out Before You Need Something

Start today. Join a professional organization and keep going back. Develop relationships with people you'd like to know, but don't ask them for a favor right away. Instead, consider why they may want to know you.

Problem: Quantity Over Quality

You share business cards everywhere you go. You have hundreds of "friends" on social media sites. That's great, but it won't take you far unless you actively cultivate at least some of those relationships.

Solution: Get Personal

"It's important to offer information to people in your network and show them you know something about them," Hamilton says. With social media, it isn't that hard to learn what a person does, what they like to do and what their interests are. From there, pick out those who can help you, who can reach people who can help you or who share your interests -- and offer them something first.

"If you think the people you want to know don't need anything from you, remember there is more than one way to offer help," Safani says. "You could let a contact know you have industry information, or information or help in one of their hobbies."

Problem: Scattershot Networking

If you don't know what you want from your career network, your contacts won't know how to help you.

Solution: Establish Clear Objectives

"It's important to do the prework of networking," says John M. O'Connor, president of Career Pro. "What do you want to get out of your network? How do you want to be perceived by others? What do you have to offer others? Answer those questions first; then take a disciplined approach and make a plan for reaching out."

Problem: Dead-End Contacts

If a new job is your goal and you're building relationships only with people who don't know many people, or who are introverted  or generally unhelpful (not returning your calls is a sign), then your network isn't working for you.

Solution: Create Targets

Susan Whitcomb, president of Career Coach Academy, recommends identifying people in companies you want to work for, or people who know people at those companies.

"Your top rung of targets should be people who have relationships with hiring managers and knowledge of the company you want," Whitcomb says. "Next best are those who have knowledge but no relationships at the company. Next are those with relationships but no knowledge. At the lower rung are people who don't know the company and don't know anyone there -- they may be good to know personally, but don't expect them to help your career."

There are many kinds of networking -- for professional goals, for personal growth or for fun. But career experts emphasize that, on the career side, networks take much care and feeding. "Networking can be like static electricity -- wasted energy -- or it can channeled for power," O'Connor says. "If you do it right, it should be like handing someone a cord and letting them plug it in."