my daughter is 20,she is a college full time student, she earned $15000 last year, I paid her half expenses,why she cannot count my dependent?

[DoninGA]

In the My Info section of the program did you indicate that she lived with you for the Whole year?  Did you indicate that she was a full time student?  Did you indicate that you provided over one-half of her support?  Did you NOT check the box labeled "not valid for employment" when entering the Social Security number?

If you answered these questions correctly, the delete her as a dependent and re-enter.

[SharonD007]

If your daughter meets the qualifying requirements of a qualifying child or a qualifying relative, then you can claim her as a dependent. Below you will find the basic qualifiers: 

To determine if the individual is your qualifying child, the following questions must be true:

• The child must be related to you. 
• The child can’t be claimed as a dependent by someone else. 
• The child must be a U.S. citizen, resident alien, national, or a Canadian or Mexican resident. 
• If the child is married, they can’t file a joint return with their spouse. 
• The child must be under the age of 19 (or 24 for full-time students). 
  • No age limit for permanently and totally disabled children. 
• The child must have lived with you for more than half the year (exceptions apply). 
• The child didn't provide more than half of their own support for the year. 

If all of your answers are yes, then you may have entered something wrong when you entered her information. 

To edit your dependent in TurboTax:

1. For TurboTax Online, go to the Personal profile screen.
2. For TurboTax Desktop, open your tax return and select Personal Info
3. Select Edit next to your dependent
4. Review your answers as DoninGA described above.

 Please review the TurboTax Help articles; Who can I claim as my dependent? and Rules for Claiming a Dependent on Your Tax Return.

[Hal_Al]

@DoninGA  said "Did you indicate that you provided over one-half of her support?"

Actually the question you should get is "did she provide more than half her own support"

As Don said, if you meet the rules, you've simply entered something wrong.  Time spend at school still counts as living with you.

There are two types of dependents, "Qualifying Children"(QC) and Other ("Qualifying Relative" in IRS parlance even though they don't have to actually be related). There is no income limit for a QC but there is an age limit, student status, a relationship test and residence test. Only a QC qualifies a taxpayer for the Earned Income Credit. They are interrelated but the rules are different for each.

The support test is different for each type. The support test, for a QC, is only that the child didn't provide more than half his own support. The support test for a Qualifying Relative is that the taxpayer provided more than half the relative's support.

A child of a taxpayer can still be a “Qualifying Child” (QC) dependent, regardless of his/her income, if:

1. He is under age 19, or under 24 if a full time student for at least 5 months of the year, or is totally & permanently disabled
2. He did not provide more than 1/2 his own support. Scholarships are excluded from the support calculation
3. He lived with the parent (including temporary absences such as away at school) for more than half the year

So, it doesn't matter how much he earned. What matters is how much he spent on support. Money he put into savings does not count as support he spent on himself.