my friends computer seems to be hacked, everytime she goes on msn, or anything else, someone knows what she has written, or done, is there a way of removing this or does she have to clean the hard drive and start all over again,
What do you mean by "someone"? Do you mean someone like a friend or colleague who might possibly have had access to the machine?. If so, they could have installed a key logger or similar spyware.
Simple answer would be to download, install and run Malwarebytes Anti-Malware.
It's free (although you can pay to get extra features, if you wish)
I think that by default MSN keeps a record of all conversations on your hard disk. I am not sure, an MSN devotee may be able to help more, but it doesn't sound like hacking. The "someone" may merely be looking at a logfile.
Someone may have got hold of her MSN password . A lot of people just use the same password for everything . Changing her MSN password & keeping it unique might be a good idea