Apple had a technical failure during a keynote demo, and it provides an important reminder for us all: always, always, always practice extensively with any technology you will be using in your presentation before you arrive at the presentation! Know how to set it up, how to operate it, how to take it apart, and have a backup plan in place for when you forget the one cable that makes the whole thing work, batteries die, or they give you a projector but no screen.
Sometimes there is no opportunity to practice, such as at a trade show where you use the projector they provide when you get there. In such cases I always bring an "emergency kit" that has all the wires I could possibly need and a flash drive with my presentation materials on it. I also keep a copy accessible online, but again, I've learned the hard way not to rely on having a good internet connection.
Lastly, remember that you don't need Powerpoint to do your presentation. Know your material well enough to speak without the slideshow if needed. It should compliment you, not the other way around.
Sometimes there is no opportunity to practice, such as at a trade show where you use the projector they provide when you get there. In such cases I always bring an "emergency kit" that has all the wires I could possibly need and a flash drive with my presentation materials on it. I also keep a copy accessible online, but again, I've learned the hard way not to rely on having a good internet connection.
Lastly, remember that you don't need Powerpoint to do your presentation. Know your material well enough to speak without the slideshow if needed. It should compliment you, not the other way around.