There could be tons of different reasons why that is happening. Delete your bin folder and re-download minecraft. If that dont work then delete the whole entire folder and then re-download.
Also you may want to reinstall java and make sure your running the latest version
whats the latest version im running windows seven compaq 30 gb system memory and 500gb memory amd athlon 11x2 215 dual core btw im reading this off the peice of paper if that makes a differnce >.> im ok at computers but i mean not with software stuff and i did what u said with minecraft
]ive system restored restarrted deleted the whole minecraft thing redownloaded it .ive done everything >.< i got on my guest account and it worked once then i reloaded it and didnt work i know i buy the game and then oneone but 2 people can help me >.<
<It is the nature of the wise to resist pleasures>
Also you may want to reinstall java and make sure your running the latest version
<It is the nature of the wise to resist pleasures>
<It is the nature of the wise to resist pleasures>