I have installed Vector yesterday, configured my ADSL connection and was browsing web pages normally.
Today after starting connection I can not load any web page like I am not online. I checked ADSL-status and everything seems normal.
What should I do?

test your connectivity. what is the output of 'ping yahoo.com' or any website?

If I try to ping any address I get a message "unreachable".
I can see in KNemo for instance, that connection is established and I got an IP address assigned.

if your ping returns 'destination unreachable' then you dont have connectivity (at least to that site).. did you try it to many reliable sites? ie yahoo.com/ca and google.com/ca ? if all of those fail, then your internet isnt working, no matter what any program says.

what is the IP address you are assigned? is it a LAN or WAN address? LAN addresses will start with something like 192.168.0.X or somethign similar. these LAN addresses dont mean your on the internet.

what NIC card do you have? is the driver/module for that card loaded? what is the output of 'ifconfig -a'? are you using a router or hub? or just connecting your computer to the aDSL modem?