shark vacuum cleaner will not turn on

If your Shark vacuum refuses to turn on, First, make sure your vacuum is plugged in. If it is plugged in and the power button is on, you may need to reset your circuit breaker. If that option doesn't work, examine the cord if it is a corded vacuum  ,if it has cuts or fraying do not try to use it, second is the on/off switch comes loose or feels that it doesn't touch the connectors .those are the main reasons your shark vacuum cleaner would not turn on.