well one reason may be that the signal shown on your wireless network in that image is really low--only 2 bars out of 5 try moving your router a bit or if its a usb wireless adaptor move that--at least 3 bars would be better but 4 or 5 would be ideal
you would have to look in your router configuration page--chances are mac address filtering wont be on unless some one else did it--if you connected wirelessly before formatting then it wont be the problem
try the easiest thing first and turn off the power to the router for 30 seconds then turn it back on
As i see from the photo,you don't have access to the network. First thing to do is to use troubleshoot tool provided by the OS (the last option down the page). If the tool is not able to tell where the problem is u have to check the adapter settings (left column of the page) and see if you have the following settings on : Follow the steps:
1. Open wireless device
2.Go to proprieties ,down the page
3. On Networking choose from the listed items Internet protocol version 4 and open proprieties
4.Check "obtain an IP address automatically and Obtain DNS....
Troubleshoot tool in rare cases fix some problems, but in most cases it shows where the problem is. Tell me if u can see something. Now... starring from the fact that you have no driver issue you have to check your modem-router settings again, and. maybe a reboot of it it my help. Is well known the fact that many "old-tech" devices have trouble to communicate with Win 7 via wireless on first attempt. To access your router you need to hook it via cable and check the wireless settings. Get in from your browser and digit 192.168.0.1 address. If it req. some name and pass ,by default,for most routers you have "admin/admin". If you have the router provided by the IP you have free access. Do this..and tell us more. I can't help without more info!