You are not supposed to seed after applying weed control. Wintergaurd (based on what I read) is mostly fertilizer. So I think it's ok to seed now (if the temp where you are does not dip below 50 degress F).

Here is what Scotts recommends: http://www.scotts.com/smg/learn/infoHowToArticle.jsp?detailId=14900060

Here is a snippet from that page:

Feeding in the Fall

Wait a minute. Isn't fall when lawns start to shut down? Why fertilize then? Fall conditions are great for lawns. Grass roots start to store nutrients the grass will need when it wakes up again in the spring. So you want to help those roots grow by fertilizing. Your best bet is to feed once in early fall (if you are overseeding, your starter fertilizer counts) and once more about 6 to 8 weeks later, around Thanksgiving. Scotts® WinterGuard® Lawn Fertilizer is formulated to deliver the nutrients grass needs to get through the winter and come up strong the following year.

What is in Scott's Winterguard besides fertilizer? If it contains a preemergent then yes, seeding now will be a waste of time and money and you will have to wait till spring. If it's just fertilizer then seeding now is fine.

You can seed
Winterguard is just a fall fertilizer.

I was looking at fertilizer on the Lowes web site I saw the following.

1- Scotts 15000 Sq. Ft. Turf Builder® WinterGuard with Plus 2 Weed Control

2- Scotts 5000 Sq. Ft. Turf Builder® WinterGuard Fall Fertilizer

I think one flavor of "Winterguard" contains preemergents (#1).
The other "Winterguard" is just fertilizer (#2).

thanks all
i used Scotts 15000 Sq. Ft. Turf Builder® WinterGuard with Plus 2 Weed Control.

If you used the one with Weed Control, you should check the package to see how long you need to wait before seeding. It's likely that you'll need to wait before seeding.