When you get up in front of an audience to present, you have to be prepared for things to go wrong. But having a Plan B for possible technical problems is not enough; you also need to have the right mindset to handle problems.
On more than one occasion I've seen speakers lose their cool when they ran into technical problems. Guess what? Complaining about the problem, cursing, or blaming the organisers of the event will not make the problem go away. But you risk losing your audience, too. Initially, the audience will be sympathetic when they realise that you're having a problem - they didn't come to see you fail! But it's your responsibility now to make the best of the situation. Complaining and stating the obvious will only put off your audience - the biggest support you'll have at that moment. Don't make that mistake.
To give you a positive example: The Creativity World Forum in Kortrijk, Belgium, was a high-profile event: Huge stage, 2800 attendees, lots of well-known speakers. So when one of the speakers found that his remote (for advancing the slides) wasn't working, it surely was a stressful moment for him. But he calmly addressed the technicians in the back of the room and suggested that they forward the slides for him (there was no PC on the stage, it was all controlled from the back) and suggested a simple hand sign for when they should do that. And it worked. It didn't even throw him off when, on one or two occasions, the slide wasn't advanced as planned - he simply gave the hand sign again.
When running into technical problems during a presentation, try to keep my mantra in mind: The audience always comes first. They came to hear you talk about your topic. They don't care so much about the beautiful slides you prepared but about hearing about the topic, from you. Does complaining about the problem help them? Of course not. So don't do that and instead think about how you can give them what they came for. If the slides don't work, use a flip chart or whiteboard. If that's not available, give a (probably abbreviated) version of your talk without slides. Or even abandon the prepared talk entirely and make it a Q&A session.
Whatever you do, though, please do try to stay calm and professional.
(The Keep Calm and Carry On poster is in the Public Domain, via WikiMedia Commons)
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