The state return can say "incomplete" if some of the state forms were not available when you tried to efile it at the same time as efiling the Federal return. If it says "incomplete", your state return has NOT been efiled. You will have to come back later to efile it.
If you mailed the Federal return, however, then the State return cannot be efiled. It would have to be filed by mail, too.
You can check on the availability of state forms here:
https://ttlc.intuit.com/questions/1908857-state-forms-availability-table-for-turbotax-individual-per...
If your Federal return has already been efiled, you will have to wait until the Federal return has been accepted before you can efile the State return. The IRS will not start processing returns until January 23, so soon after that date you should hear if your Federal return is accepted or rejected. (A few returns will be pulled by the IRS before then for testing purposes so some people may get an early acceptance/rejection notice.)
So once your Federal return (if efiled) has been accepted, and IF all your state forms are then available, you can then go back and open up your State return to complete, review, and efile it.A state return can only be efiled if it is efiled at the same time as the Federal is efiled, or if the Federal has already been efiled and accepted. This rule was placed in effect last year when there were so many fraudulent state returns being efiled by themselves.
If a Federal return is mailed, then the State return has to be mailed.
The state return can say "incomplete" if some of the state forms were not available when you tried to efile it at the same time as efiling the Federal return. If it says "incomplete", your state return has NOT been efiled. You will have to come back later to efile it.
If you mailed the Federal return, however, then the State return cannot be efiled. It would have to be filed by mail, too.
You can check on the availability of state forms here:
https://ttlc.intuit.com/questions/1908857-state-forms-availability-table-for-turbotax-individual-per...
If your Federal return has already been efiled, you will have to wait until the Federal return has been accepted before you can efile the State return. The IRS will not start processing returns until January 23, so soon after that date you should hear if your Federal return is accepted or rejected. (A few returns will be pulled by the IRS before then for testing purposes so some people may get an early acceptance/rejection notice.)
So once your Federal return (if efiled) has been accepted, and IF all your state forms are then available, you can then go back and open up your State return to complete, review, and efile it.