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http://askubuntu.com – I installed ubuntu using Usb(pen drive) but 1st time i could not download all updates...but it "appears restart now".. then I restart my computer..( but still I connected my usb drive.) after restart my laptop it normally opened win 7....!!!!!!! not any message to choose the program(win or ubuntu) but still I can open ubuntu after connect my usb drive.... now i insta plz tell me how i can solve this problem (HowTos)