laptop booting problem

[Amit Tiwari]

i have a dell vostro..i had installed win 10 tech preview on it..some files got expired..concluding it to crash windows. m trying to boot with the help of usb..its not booting now

 

[hang-the-9]

Need more details, boot to what type of USB? What are you trying to do exactly and what is happening, with any error messages?