From saying the wrong thing during a phone screening to forgetting a key piece of information about a potential employer during a face-to-face interview, a single misstep can ruin any chance an applicant might have at getting hired.

Here are seven major mistakes a job candidate might make that can prolong a job search.

Talking Too Much

At the onset of a job search, it's natural for a applicant to want to give 110%. Be mindful, however, that being too eager can hurt you just as much as not trying at all.

Pushy job-seekers sometimes have a tendency to over-speak during phone interviews in an effort to play up their strengths.

When the phone rings and a recruiter is on the other end, try to contain yourself. Don't start gushing about your professional experience right away. Take a deep breath, listen carefully to what is being asked of you and only answer those questions. Remember not to give one-word responses, but don' t tell your life story, either. If a company is interested, you'll have plenty of time to discuss all sorts of fascinating topics and share more of your background in a face-to-face meeting.

Not Knowing Your Market Value

Job candidates who don't research current salary ranges in their respective fields are setting themselves up for disaster. Not doing this can put you in a position in which your asking price is either too low or too high.

Before you even begin to apply to jobs, you should have a strong knowledge of how much people like you are getting paid at companies like the ones you're targeting.

Visit sites like Salary.com, Payscale.com and Glassdoor.com to find out how much your skills are worth. That way, when a hiring manager asks, "What are you looking to earn?", you'll be able to respond with a solid number. You should also update your resume and include reminders throughout of the dollars you have earned or saved for previous employers, and be sure to note the big projects you?ve worked on.

Keeping Your Network in the Dark

Don't forget to share with people you know -- personally and professionally -- that you're embarking on a new job search. Keeping them out of the loop on your potential career move could cause you to miss out on promising job opportunities.

At least one-third of your job-search strategy should be dedicated to networking. An easy way to reconnect with old friends and former colleagues is through social networking sites like Facebook and LinkedIn. Let them know specifically the types of positions you're looking for, keep them posted on the employers you're targeting, and allow them to introduce you to other people who can help move your job-search along.

Showing Up Unprepared

In the age of the Internet, there's no excuse for going to an interview without having some prior knowledge of an organization's history, its competitors and its industry's current challenges.

Also, you'll want to have at least five to ten questions prepared that speak to the employer's situation in the marketplace and the impact of the role you're interviewing for on that equation.

Instead of asking, "What does your business do?", you can say something like, "It seems that the traditional distribution model for your products is changing incredibly fast. How are you dealing with that issue?" Not doing these things puts you at an immediate disadvantage when compared to the dozens of other applicants who've done their research, and it shows a lack of serious interest in the company.

Losing Focus During an Interview

It's natural to feel a bit nervous before an interview. What's not OK is to let those nerves get the best of you when meeting face-to-face with a hiring manager.

Remember to stay focused on the conversation at hand, even though your mind might be screaming "Was that a good answer?" A clear sign that you're losing your cool is rambling. Dragging on about one topic is not the best way to present yourself.

Employers hire people they have confidence in, not people who second-guess themselves. As the interviewer asks you a question, ask yourself, "What does he really want to learn through my answer?" That will help you compose a response that is thoughtful and concise.

Not Being Accountable

Most applicants have at least one blemish on their resume. Employers expect this. You've got to anticipate questions related to that flaw and be ready to respond.

If you've changed jobs frequently, switched industries more than once or taken off an extended period of time between jobs, be prepared to answer, "What's the story behind this move?" Not being able to clearly explain something, such as why you've been unemployed for the past year, is going to raise a red flag.

Prior to an interview, take time to talk through every step of your career history with a friend who can help you construct fluid answers to any question an interviewer might pose about your background. The key is not to apologize for your career twists and turns, but rather integrate them into your story. If you're coming back from a few years out of the workforce due to raising kids, for instance, you can say "I've been home with my twins since 2007, and I'm chomping at the bit to get back into online marketing and build site traffic for a natural-food-products company."

Jumping the Gun on a Job Offer

Getting a job offer after a lengthy search can be exciting. However, accepting an offer before you've had time to fully consider the terms -- from the reporting structure to health benefits to base pay -- isn't smart.

Be wary of employers who only give you a day or two to evaluate an offer, and especially so if they're hesitant to put it in writing. Say to the hiring manager, "This is fantastic. There are a lot of moving parts, so I'd love to get the offer in writing and be able to review it carefully." Remember, you can't negotiate the job terms if you aren't aware of what's exactly on the table.

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