Ok.

My main pc downstairs has Vista on it and the pc upstairs has XP.

The internet is run through cable downstairs and also has wireless set up.

The Vista pc will not connect to the internet, but the XP pc will connect fine (as I am on it now). It stopped working downstairs on Sunday.

I am not really that PC smart when it comes to fixing the internet and I really don't know what has happened. Would anyone have any ideas? Maybe my mum has accidentally blocked it out or something?

Please help.

First, Welcome.

Can you give me some more details on your problem and your method of connection. Are you using a wireless router. Also can you start a command prompt and run an ipconfig and paste in a reply post that will help us run this down with you..

all the best.

josh

The vista computer is connected with a cable and has a wireless router. The xp computer is using the wireless and is fine.

It came back on last Thursday but has knocked off again on the Vista computer only.

Im sorry but I am not computer friendly, to a certain extent yeah, but I do not know how to run a command prompt or anything. 

So there is a chance that it is related to the driver for your wireless card.  I would update that first.  To do that find the make and model and visit the vendors web site and get the latest driver and install it.