They "tried to get me to run commands in the black screen which would not work so" that means that your machine can't use these commands or the OS is corrupted.
Time for a tech call it seems or try tools like you read at http://forums.cnet.com/5208-6132_102-0.html?forumID=32&threadID=238606&messageID=2432058 and add IEFIX at the end to see if you can DO IT YOURSELF to fix the OS.
Bob
I'm using xp i have telstra cable connected via earthnet to my computer the computer connects to the network at 100mbps but will not get Internet or email telstra say that they can see there modem and it is working OK she tried to get me to run commands in the black screen which would not work so blames my computer me I'm desperately trying to fix as i need it for my study any ideas would really be appreciated

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