Maybe your router blocks out your computer?
Why should it block the laptop from one day to another???
I suspect your DNS settings.
Reminds me of the DNS-changer-virus!
How to get known what's wrong with it and how to fix it?
Make sure the clock is correct. Some computers and routers can behave strange when the clock is wrong, especially when the year is wrong.
Only 12sec difference from the other computer!
New strange facts:
On skype, I still see, who is online and who isn't!
Only sorunome, who was on "away" before he went offline, isn't shown correctly!
is online mode always changes between "away" and "offline"
I can even click on "videocall" which is only possible of the other guy is online!
but on the other computer I saw that he was offline all the time!
When he went online again,he called me in skype!
but it was also telling me on the laptop that he's calling me!
I was even able to talk to him, using the laptop!! O.o
after I quit the call, everything was as strange as before again!