usb wont boot

[shashank5]

earlier i was able to boot from usb ubuntu . now same computer i am not able to boot fromusb in win 7 OS. ubuntu usb boots in other computers

[HMN]

When you power on the computer, you can press a certain key (e.g. esc) to prompt you with boot options. Then you select booting from the usb. On the other hand, you can enter the BIOS after powering on and choose usb as your first boot option.

[shashank5]

yes i tried but still it doesnt boot, tried on others computers it boots. even it doesnt show 'install ubuntu' in my computer other computers it shows with ubuntu icon

[HMN]

Press the special key to bring the boot options. If you dont see your usb listed, hit ctrl/alt/del to reboot while the usb is still attached. Press the special key to bring the boot options again, and you should see the usb listed--probably in listed twice, one with efi support.

[shashank5]

win 7 OS. usb listed but doesnt boot earlier, it was booting by selecting usb in boot options i don't know why it stopped booting