You didn't tell much but read a similar failure and fix at http://forums.cnet.com/5208-7587_102-0.html?forumID=69&threadID=324874&messageID=2950475&tag=forums06;forum-threads
Will not finish boot. Stops at [press ctrl-alt-del keys to continue window], default. I got into DOS screen but it is frozen, I can't get it into Safe Mode and it times me out and leaves screen

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