Windows 7: unidentified network(can't obtain ip address)

everything's set to automatic. don't I have one ip for all networks?

Might be worth giving it a shot to assign Static IPs instead of DHCP to the WLAN setting, it might do a miracle.
How to Assign a Static IP Address in XP, Vista, or Windows 7 - How-To Geek

Please let us know if it works or not.

You will have one IP address for all networks when you set up a Static IP address as suggested, when are obtaining a IP address from the DHCP server, you are getting given a random IP address at every boot.

Follow the tutorial suggested by 2xg, and please post back your results.

um where I can get the settings i should write there?

edaz - find a working computer connected to your router or your network then run ipconfig /all. You will use the pattern of the output and assign it in your computer, but you'll have to change the last digit of the TCP/IP. Here's a different Tutorial, perhaps it might help you understand better.
Setting a Static IP Address in Windows 7 - PortForward.com

If you still can't follow the Tutorial, please post the ipconfig/all output coming from another working computer and we'll help you with the Static IP assignment.

Follow 2xg's tutorial, but if that doesn't work, I have another suggestion with the Firewall settings. Since the DHCP server, uses UDP/67 and UDP/68 ports, then make sure these ports are allowed access through your Windows Firewall, this can be achieved with this tutorial:

How to Open a Port in the Windows 7 Firewall

Didnt have time to try adding static ip, but today connection started working again. It seems that my ip has changed, although i dunno why it changed and why it didnt change sooner, last reboot i did was about 2 days ago =] anyway thanks for your help

That's good to hear, hopefully the connection will remain normal (:

Thanks for informing us!

Thanks for letting us know edaz, that's good news!