Connecting a Buzzer to a PIC

This time I'm Building a Serial Code Lock With PIC 16F84A...

I need to connect a buzzer to the PIC to hear my Keypad Tones All the time I Used Piezo Plates & Diaphrams....I hate the OLd ODD sound coming from the piezo...

So I Connected a buzzer Listed below... .When u checking the buzzer with a multimeter its giving a nice sound.... but when u connect the buzzer to the PIC its not working well..sometimes its not working....

How can I connect the buzzer to the PIC to get a nice keypad tones.

I Connected a buzzer through a transistor NPN,PNP & Without Transistor...but didn't work well even I Changed 4 Buzzers...Some times the sound is coming only one time....after that no more sound...

If that really is a 'buzzer' it's designed to do one thing.. Buzz. Sounds like it's a piezo buzzer with a built in driver that just requires power to run. You're never going to get anything more than a simple buzz out of that kind of device.