Btw. a couple of day after originally posting this thread, it just didn't happen anymore (I had then had the pc at the IT-guys, but they said they didn't do anything with it...). I got it back and nothing has been blocked since that...
the IT-guy at my school sent a mail to the "AV expert"... This is the answer:
Which webpages that works in Chrome or Mozilla do we not give support on.
We only give support for IE8.
He gets a denial of service attack from his own router.
That means that it is either the page he is trying to visit that does something, or there is another computer that is trying to infect his machine (it can be one in the same house or another client that has the same ISP provider). A test can be done by checking if it happens in the school network.
If not, it is probably another PC that is causing the problem.
(It has happened ONE time in the school network..)
But I tried to have all the pc's off (exept my dads, which MIGHT have just been closed instead of off, but that pretty much the same?) when I used the school pc and the net still got blocked... So it cant be another pc?
And how could it be one from the same ISP provider?
+ I think I remember it happening when I visited my brother too... I'm not sure
+ I have talked to one guy at my school it happens too, one I know at another school (he just kept turning internet protection off everytime until it didnt happen anymore) and another one...
Could it be a update that fixed it? That something was wrong and got fixed that way?
(this HAS happened before too, but then it just went away after a while like it did this time...)
I know, I know the problem is fixed, but I'm curious WHY it happened in the first place....
thank you for answers :)