What are the most common technical issues during a presentation?

Always check your battery pack, headset, etc. in a quick soundcheck on stage including all your slides and especially all video content. Have a separate handheld microphone ready in a corner of the stage or inside the lectern, so that backup is assured in case something goes wrong.

In addition to ensuring equipment functionality, walk the room during sound check. Everything may sound great when you are front-and-center, but you may find that your microphone is out-of-range in some areas or that annoying feedback is produced in others. This is especially true if you walk near a speaker or another microphone. Find these issues out in advance--your audience will thank you!

Don't make assumptions! Ask in advance about computer hardware (PC vs. Mac, yours vs. theirs), connections, presentation format, screen size, and screen aspect ratio (4:3 or 16:9). Prepare accordingly AND have backups in case things change. Whenever possible, I present from my own personal MacBook. This eliminates compatibility issues between my file and their computer and between remotes. I bring a few connection options and always have a spare HDMI cable. I present from Keynote (Mac), but will also have a version of the presentation in PDF format on a USB drive and in the cloud. This way, if I need to present from another device, there are no format issues. If everything fails, the audience can access the visuals from their phone.

You should also prepare to do without your slides altogether in case there is a tech issue. Having a solid structure, good examples, stories, data or anecdotes and most importantly a clear idea of the point of your presentation (what you want the audience to think, feel or do) will ensure that your presentation doesn’t rely on your slides, so any technical glitches won’t be a major problem in you getting your message across.

Have a plan B and C in place. I am always ready with an offline version of an online presentation and have some bullet points at hand in case everything fails and I need to present without any visual aids. Having planed for the worst, makes sure you'll rock the stage with a small and keep your audience entertained no matter what goes wrong.

Try not to rely on internet connectivity for in-person presentations. Wi-Fi is notoriously bad at convention centers, especially if hundreds or thousands of people are trying to use it simultaneously. Download what you can to your device. If you need to show a webpage, you can preload the site before the presentation. If you need to demonstrate something online, consider screen recording the demonstration beforehand and embedding the video in your presentation. If there are internet issues, you can quickly switch to the video and talk through it without missing a beat. It may be so smooth that the audience doesn't notice--but if they do, they will appreciate that you came prepared for the worst!

A few days before your presentation, ensure your operating system and software are up-to-date. Save a version of your presentation on your hard drive (in case of internet connectivity issues), in the cloud (in case your computer is lost or broken), and on a USB (to easily transfer to another device). Save it in multiple formats, including PDF (universal, preserves fonts). Before you present, ensure all unnecessary applications are closed on your computer and turn off all notifications (maximize system resources and minimize distraction or embarrassment).

If anything goes wrong and your audience notices, do not try to hide the mistake. Your audience gets as tense as you do, so help them relax, smile and say something like "Well, that did not go as planned...so let's try this again". If you can even relate the mistake and the fix to a lesson to be learned from your presentation, even better.

Si algo falla, tratar de darle solución, de otra manera, seguir adelante con la presentación y utilizar los recursos que queden disponibles.