4. Watch out for phantom money

Lohrenz says consumers with a history of collections can have their outstanding balances appear larger than they actually are because of the booming secondary market for collections. Here's how it happens: If a consumer has a credit card balance that becomes delinquent, the issuer will attempt to collect for a while, then give up and sell the account to a collection agency.

The card balance should then drop to zero, and a new account, this time with the collection agency, should appear on the report. Sometimes, though, the issuer won't strike that balance from its records, and it will appear as if the consumer has two outstanding debts. If the debt is bought and sold numerous times, which is common, the problem can multiply.

Another instance of "phantom money" can occur when a consumer has a closed bank account that had an overdraft protection line of credit. In some instances, that line of credit will remain on a person's report even after the account is closed, says Bucci.

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5. Dispute any mistakes

If you find a major mistake, order your credit report from all three bureaus. Doing so can help you figure out if the problem is limited to just one report. The next thing to determine is if you need to take your dispute up with the credit-reporting bureau or the lender.

If there's a case of mistaken identity, such as someone else's information on your report, or accounts listed that aren't familiar to you, contact the bureau. All three bureaus have online dispute forms, which Sweet says are faster than snail mail for resolving problems.

"Taking things up with the bureau is easier because they have one set process," says Bucci. "There's a dispute process in place, so you can dispute any account with the same process, whereas when you contact the creditor, every one's a little different. It's not as neat and simple."

In the case of negative information more than seven years old or a report of an outstanding balance that has actually been paid off, try contacting the lender directly.

6. Follow up

It would be great if you could just file a dispute and forget about it, but you may have to follow up. Especially if an item is very old, the creditor in question may have been bought, merged or gone out of business entirely, which makes documenting everything important.

Keep notes of the people you speak with at the bureau or lender, when you contacted them and the date by which any corrective action is to be taken. Check your credit report again after that date to make sure they followed through. The three credit bureaus communicate with each other electronically, so a correction made on one report should be reflected on the other versions, too.

7. What not to sweat

There are a couple of items pertaining to your credit report that might seem alarming but really aren't a big deal. Closed accounts in good standing don't need to be taken off your report. In fact, leaving them on your report can help.

Credit inquiries also aren't as damaging as many people believe, says Sweet. "Honestly, a hard inquiry is very small impact on your credit score, and it's short term. It stays on for two years, but it has the most impact only within six months." A "hard" inquiry will appear if you applied for a loan or credit card. It can also crop up if you enter into a service contract such as a cellphone or cable-TV plan.

Lohrenz says not to worry about the actual credit scores, the three-digit numbers lenders use to gauge your level of risk. It's what the report contains that dictates your score, so concentrate on making sure it's accurate and up to date.

This article was reported by Martha White for Bankrate.com.